Niklas Schnelle [Fri, 25 Feb 2022 08:45:24 +0000 (09:45 +0100)]
s390/pci: add error record for CC 2 retries
Currently it is not detectable from within Linux when PCI instructions
are retried because of a busy condition. Detecting such conditions and
especially how long they lasted can however be quite useful in problem
determination. This patch enables this by adding an s390dbf error log
when a CC 2 is first encountered as well as after the retried
instruction.
Despite being unlikely it may be possible that these added debug
messages drown out important other messages so allow setting the debug
level in zpci_err_insn*() and set their level to 1 so they can be
filtered out if need be.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Niklas Schnelle [Thu, 24 Feb 2022 14:45:33 +0000 (15:45 +0100)]
s390/pci: add PCI access type and length to error records
Currently when a PCI instruction returns a non-zero condition code it
can be very hard to tell from the s390dbf logs what kind of instruction
was executed. In case of PCI memory I/O (MIO) instructions it is even
impossible to tell if we attempted a load, store or block store or how
large the access was because only the address is logged.
Improve this by adding an indicator byte for the instruction type to the
error record and also store the length of the access for MIO
instructions where this can not be deduced from the request.
We use the following indicator values:
- 'l': PCI load
- 's': PCI store
- 'b': PCI store block
- 'L': PCI load (MIO)
- 'S': PCI store (MIO)
- 'B': PCI store block (MIO)
- 'M': MPCIFC
- 'R': RPCIT
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Availability events are logged in s390dbf in s390dbf/pci_error/hex_ascii
even though they don't indicate an error condition.
They have also become redundant as commit cc66183319ad5 ("s390/pci: add
simpler s390dbf traces for events") added an s390dbf/pci_msg/sprintf log
entry for availability events which contains all non reserved fields of
struct zpci_ccdf_avail. On the other hand the availability entries in
the error log make it easy to miss actual errors and may even overwrite
error entries if the message buffer wraps.
Thus simply remove the availability events from the error log thereby
establishing the rule that any content in s390dbf/pci_error indicates
some kind of error.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Niklas Schnelle [Fri, 18 Mar 2022 15:25:31 +0000 (16:25 +0100)]
s390/pci: make better use of zpci_dbg() levels
While the zpci_dbg() macro offers a level parameter this is currently
largely unused. The only instance with higher importance than 3 is the
UID checking change debug message which is not actually more important
as the UID uniqueness guarantee is already exposed in sysfs so this
should rather be 3 as well.
On the other hand the "add ..." message which shows what devices are
visible at the lowest level is essential during problem determination.
By setting its level to 1, lowering the debug level can act as a filter
to only show the available functions.
On the error side the default level is set to 6 while all existing
messages are printed at level 0. This is inconsistent and means there is
no room for having messages be invisible on the default level so instead
set the default level to 3 like for errors matching the default for
debug messages.
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
The vfio_ap module tries to register for the vfio_ap bus - but that's
the interface that it provides itself, so this does not make much sense,
thus let's simply drop this statement now.
Sven Schnelle [Wed, 6 Apr 2022 07:17:21 +0000 (09:17 +0200)]
s390/vdso: add vdso randomization
Randomize the address of vdso if randomize_va_space is enabled.
Note that this keeps the vdso address on the same PMD as the stack
to avoid allocating an extra page table just for vdso.
Sven Schnelle [Wed, 6 Apr 2022 06:44:49 +0000 (08:44 +0200)]
s390/vdso: map vdso above stack
In the current code vdso is mapped below the stack. This is
problematic when programs mapped to the top of the address space
are allocating a lot of memory, because the heap will clash with
the vdso. To avoid this map the vdso above the stack and move
STACK_TOP so that it all fits into three level paging.
Sven Schnelle [Wed, 6 Apr 2022 06:35:26 +0000 (08:35 +0200)]
s390/vdso: move vdso mapping to its own function
This is a preparation patch for adding vdso randomization to s390.
It adds a function vdso_size(), which will be used later in calculating
the STACK_TOP value. It also moves the vdso mapping into a new function
vdso_map(), to keep the code similar to other architectures.
Sven Schnelle [Wed, 6 Apr 2022 06:01:24 +0000 (08:01 +0200)]
s390/mmap: increase stack/mmap gap to 128MB
This basically reverts commit b747b902067b ("[S390] reduce miminum
gap between stack and mmap_base"). 32MB is not enough space
between stack and mmap for some programs. Given that compat
task aren't common these days, lets revert back to 128MB.
This patch tries to fix as much as possible of the
checkpatch.pl --strict findings:
CHECK: Logical continuations should be on the previous line
CHECK: No space is necessary after a cast
CHECK: Alignment should match open parenthesis
CHECK: 'useable' may be misspelled - perhaps 'usable'?
WARNING: Possible repeated word: 'is'
CHECK: spaces preferred around that '*' (ctx:VxV)
CHECK: Comparison to NULL could be written "!msg"
CHECK: Prefer kzalloc(sizeof(*zc)...) over kzalloc(sizeof(struct...)...)
CHECK: Unnecessary parentheses around resp_type->work
CHECK: Avoid CamelCase: <xcRB>
There is no functional change comming with this patch, only
code cleanup, renaming, whitespaces, indenting, ... but no
semantic change in any way. Also the API (zcrypt and pkey
header file) is semantically unchanged.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This patch does a little cleanup on the CPRBX struct
in zcrypt.h and the redundant CPRB struct definition in
zcrypt_msgtype6.c. Especially some of the misleading
fields from the CPRBX struct have been removed.
There is no semantic change coming with this patch.
The field names changed in the XCRB struct are only related
to reserved fields which should never been used.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
This patch introduces user space notifications for changes
on the apmask or aqmask attributes. So it could be possible
to write a udev rule to load/unload the vfio_ap kernel module
based on changes of these masks.
On chance of the apmask or aqmask an AP change event will
be produced with an uevent environment variable showing
the new APMASK or AQMASK mask.
So a change on the apmask triggers an uvevent like this:
Only real changes to the masks are processed - the old and
new masks are compared and no action is done if the values
are equal (and thus no uevent). The emit of the uevent is
the very last action done when a mask change is processed.
However, there is no guarantee that all unbind/bind actions
caused by the apmask/aqmask changes are completed when the
apmask/aqmask change uevent is received in userspace.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Tested-by: Thomas Huth <thuth@redhat.com> Reviewed-by: Jürgen Christ <jchrist@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
s390/zcrypt: add display of ASYM master key verification pattern
This patch extends the sysfs attribute mkvps for CCA cards
to show the states and master key verification patterns for
the old, current and new ASYM master key registers.
With this patch now all relevant master key verification
patterns related to a CCA HSM are available with the mkvps
sysfs attribute. This is a requirement for some exploiters
like the kubernetes cex plugin or initrd code needing to
verify the master key verification patterns on HSMs before
use.
s390/kexec: set end-of-ipl flag in last diag308 call
If the facility IPL-complete-control is present then the last diag308
call made by kexec shall set the end-of-ipl flag in the subcode register
to signal the hypervisor that this is the last diag308 call made by Linux.
Only the diag308 calls made during a regular kexec need to set
the end-of-ipl flag, in all other cases the hypervisor will ignore it.
Merge tag 'perf_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- Add Sapphire Rapids CPU support
- Fix a perf vmalloc-ed buffer mapping error (PERF_USE_VMALLOC in use)
* tag 'perf_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/cstate: Add SAPPHIRERAPIDS_X CPU support
perf/core: Fix perf_mmap fail when CONFIG_PERF_USE_VMALLOC enabled
Merge tag 'edac_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras
Pull EDAC fix from Borislav Petkov:
- Read the reported error count from the proper register on
synopsys_edac
* tag 'edac_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ras/ras:
EDAC/synopsys: Read the error count from the correct register
kvmalloc: use vmalloc_huge for vmalloc allocations
Since commit c896ce72c681 ("vmalloc: replace VM_NO_HUGE_VMAP with
VM_ALLOW_HUGE_VMAP"), the use of hugepage mappings for vmalloc is an
opt-in strategy, because it caused a number of problems that weren't
noticed until x86 enabled it too.
One of the issues was fixed by Nick Piggin in commit 44a4793d6c1c
("mm/vmalloc: huge vmalloc backing pages should be split rather than
compound"), but I'm still worried about page protection issues, and
VM_FLUSH_RESET_PERMS in particular.
However, like the hash table allocation case (commit d06f267d2bd4:
"page_alloc: use vmalloc_huge for large system hash"), the use of
kvmalloc() should be safe from any such games, since the returned
pointer might be a SLUB allocation, and as such no user should
reasonably be using it in any odd ways.
We also know that the allocations are fairly large, since it falls back
to the vmalloc case only when a kmalloc() fails. So using a hugepage
mapping seems both safe and relevant.
This patch does show a weakness in the opt-in strategy: since the opt-in
flag is in the 'vm_flags', not the usual gfp_t allocation flags, very
few of the usual interfaces actually expose it.
That's not much of an issue in this case that already used one of the
fairly specialized low-level vmalloc interfaces for the allocation, but
for a lot of other vmalloc() users that might want to opt in, it's going
to be very inconvenient.
We'll either have to fix any compatibility problems, or expose it in the
gfp flags (__GFP_COMP would have made a lot of sense) to allow normal
vmalloc() users to use hugepage mappings. That said, the cases that
really matter were probably already taken care of by the hash tabel
allocation.
Song Liu [Fri, 15 Apr 2022 16:44:11 +0000 (09:44 -0700)]
page_alloc: use vmalloc_huge for large system hash
Use vmalloc_huge() in alloc_large_system_hash() so that large system
hash (>= PMD_SIZE) could benefit from huge pages.
Note that vmalloc_huge only allocates huge pages for systems with
HAVE_ARCH_HUGE_VMALLOC.
Signed-off-by: Song Liu <song@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Rik van Riel <riel@surriel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge tag '5.18-rc3-ksmbd-fixes' of git://git.samba.org/ksmbd
Pull ksmbd server fixes from Steve French:
- cap maximum sector size reported to avoid mount problems
- reference count fix
- fix filename rename race
* tag '5.18-rc3-ksmbd-fixes' of git://git.samba.org/ksmbd:
ksmbd: set fixed sector size to FS_SECTOR_SIZE_INFORMATION
ksmbd: increment reference count of parent fp
ksmbd: remove filename in ksmbd_file
Merge tag 'arc-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
- Assorted fixes
* tag 'arc-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: remove redundant READ_ONCE() in cmpxchg loop
ARC: atomic: cleanup atomic-llsc definitions
arc: drop definitions of pgd_index() and pgd_offset{, _k}() entirely
ARC: dts: align SPI NOR node name with dtschema
ARC: Remove a redundant memset()
ARC: fix typos in comments
ARC: entry: fix syscall_trace_exit argument
Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fix from James Bottomley:
"One fix for an information leak caused by copying a buffer to
userspace without checking for error first in the sr driver"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: sr: Do not leak information in ioctl
Merge tag 'for-linus-5.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip
Pull xen fixes from Juergen Gross:
"A simple cleanup patch and a refcount fix for Xen on Arm"
* tag 'for-linus-5.18-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
arm/xen: Fix some refcount leaks
xen: Convert kmap() to kmap_local_page()
Merge tag 'drm-fixes-2022-04-23' of git://anongit.freedesktop.org/drm/drm
Pull more drm fixes from Dave Airlie:
"Maarten was away, so Maxine stepped up and sent me the drm-fixes
merge, so no point leaving it for another week.
The big change is an OF revert around bridge/panels, it may have some
driver fallout, but hopefully this revert gets them shook out in the
next week easier.
Otherwise it's a bunch of locking/refcounts across drivers, a radeon
dma_resv logic fix and some raspberry pi panel fixes.
panel:
- revert of patch that broke panel/bridge issues
dma-buf:
- remove unused header file.
amdgpu:
- partial revert of locking change
radeon:
- fix dma_resv logic inversion
panel:
- pi touchscreen panel init fixes
vc4:
- build fix
- runtime pm refcount fix
vmwgfx:
- refcounting fix"
* tag 'drm-fixes-2022-04-23' of git://anongit.freedesktop.org/drm/drm:
drm/amdgpu: partial revert "remove ctx->lock" v2
Revert "drm: of: Lookup if child node has panel or bridge"
Revert "drm: of: Properly try all possible cases for bridge/panel detection"
drm/vc4: Use pm_runtime_resume_and_get to fix pm_runtime_get_sync() usage
drm/vmwgfx: Fix gem refcounting and memory evictions
drm/vc4: Fix build error when CONFIG_DRM_VC4=y && CONFIG_RASPBERRYPI_FIRMWARE=m
drm/panel/raspberrypi-touchscreen: Initialise the bridge in prepare
drm/panel/raspberrypi-touchscreen: Avoid NULL deref if not initialised
dma-buf-map: remove renamed header file
drm/radeon: fix logic inversion in radeon_sync_resv
Merge tag 'block-5.18-2022-04-22' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Just two small regression fixes for bcache"
* tag 'block-5.18-2022-04-22' of git://git.kernel.dk/linux-block:
bcache: fix wrong bdev parameter when calling bio_alloc_clone() in do_bio_hook()
bcache: put bch_bio_map() back to correct location in journal_write_unlocked()
Merge tag 'io_uring-5.18-2022-04-22' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
"Just two small fixes - one fixing a potential leak for the iovec for
larger requests added in this cycle, and one fixing a theoretical leak
with CQE_SKIP and IOPOLL"
* tag 'io_uring-5.18-2022-04-22' of git://git.kernel.dk/linux-block:
io_uring: fix leaks on IOPOLL and CQE_SKIP
io_uring: free iovec if file assignment fails
Merge tag 'perf-tools-fixes-for-v5.18-2022-04-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix header include for LLVM >= 14 when building with libclang.
- Allow access to 'data_src' for auxtrace in 'perf script' with ARM SPE
perf.data files, fixing processing data with such attributes.
- Fix error message for test case 71 ("Convert perf time to TSC") on
s390, where it is not supported.
* tag 'perf-tools-fixes-for-v5.18-2022-04-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf test: Fix error message for test case 71 on s390, where it is not supported
perf report: Set PERF_SAMPLE_DATA_SRC bit for Arm SPE event
perf script: Always allow field 'data_src' for auxtrace
perf clang: Fix header include for LLVM >= 14
Randy Dunlap [Sat, 23 Apr 2022 03:25:17 +0000 (20:25 -0700)]
sparc: cacheflush_32.h needs struct page
Add a struct page forward declaration to cacheflush_32.h.
Fixes this build warning:
CC drivers/crypto/xilinx/zynqmp-sha.o
In file included from arch/sparc/include/asm/cacheflush.h:11,
from include/linux/cacheflush.h:5,
from drivers/crypto/xilinx/zynqmp-sha.c:6:
arch/sparc/include/asm/cacheflush_32.h:38:37: warning: 'struct page' declared inside parameter list will not be visible outside of this definition or declaration
38 | void sparc_flush_page_to_ram(struct page *page);
Exposed by commit ba4d4c1dbb12 ("crypto: xilinx - Turn SHA into a
tristate and allow COMPILE_TEST") but not Fixes: that commit because the
underlying problem is older.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Reported-by: kernel test robot <lkp@intel.com> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: David S. Miller <davem@davemloft.net> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: sparclinux@vger.kernel.org Acked-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Airlie [Sat, 23 Apr 2022 05:00:33 +0000 (15:00 +1000)]
Merge tag 'drm-misc-fixes-2022-04-22' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes
Two fixes for the raspberrypi panel initialisation, one fix for a logic
inversion in radeon, a build and pm refcounting fix for vc4, two reverts
for drm_of_get_bridge that caused a number of regression and a locking
regression for amdgpu.
Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Fix some syzbot-detected bugs, as well as other bugs found by I/O
injection testing.
Change ext4's fallocate to consistently drop set[ug]id bits when an
fallocate operation might possibly change the user-visible contents of
a file.
Also, improve handling of potentially invalid values in the the
s_overhead_cluster superblock field to avoid ext4 returning a negative
number of free blocks"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
jbd2: fix a potential race while discarding reserved buffers after an abort
ext4: update the cached overhead value in the superblock
ext4: force overhead calculation if the s_overhead_cluster makes no sense
ext4: fix overhead calculation to account for the reserved gdt blocks
ext4, doc: fix incorrect h_reserved size
ext4: limit length to bitmap_maxbytes - blocksize in punch_hole
ext4: fix use-after-free in ext4_search_dir
ext4: fix bug_on in start_this_handle during umount filesystem
ext4: fix symlink file size not match to file content
ext4: fix fallocate to use file_modified to update permissions consistently
Merge tag 'ata-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata
Pull ATA fix from Damien Le Moal:
"A single fix to avoid a NULL pointer dereference in the pata_marvell
driver with adapters not supporting DMA, from Zheyu"
* tag 'ata-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata:
ata: pata_marvell: Check the 'bmdma_addr' beforing reading
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm fixes from Paolo Bonzini:
"The main and larger change here is a workaround for AMD's lack of
cache coherency for encrypted-memory guests.
I have another patch pending, but it's waiting for review from the
architecture maintainers.
RISC-V:
- Remove 's' & 'u' as valid ISA extension
- Do not allow disabling the base extensions 'i'/'m'/'a'/'c'
x86:
- Fix NMI watchdog in guests on AMD
- Fix for SEV cache incoherency issues
- Don't re-acquire SRCU lock in complete_emulated_io()
- Avoid NULL pointer deref if VM creation fails
- Fix race conditions between APICv disabling and vCPU creation
- Bugfixes for disabling of APICv
- Preserve BSP MSR_KVM_POLL_CONTROL across suspend/resume
selftests:
- Do not use bitfields larger than 32-bits, they differ between GCC
and clang"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
kvm: selftests: introduce and use more page size-related constants
kvm: selftests: do not use bitfields larger than 32-bits for PTEs
KVM: SEV: add cache flush to solve SEV cache incoherency issues
KVM: SVM: Flush when freeing encrypted pages even on SME_COHERENT CPUs
KVM: SVM: Simplify and harden helper to flush SEV guest page(s)
KVM: selftests: Silence compiler warning in the kvm_page_table_test
KVM: x86/pmu: Update AMD PMC sample period to fix guest NMI-watchdog
x86/kvm: Preserve BSP MSR_KVM_POLL_CONTROL across suspend/resume
KVM: SPDX style and spelling fixes
KVM: x86: Skip KVM_GUESTDBG_BLOCKIRQ APICv update if APICv is disabled
KVM: x86: Pend KVM_REQ_APICV_UPDATE during vCPU creation to fix a race
KVM: nVMX: Defer APICv updates while L2 is active until L1 is active
KVM: x86: Tag APICv DISABLE inhibit, not ABSENT, if APICv is disabled
KVM: Initialize debugfs_dentry when a VM is created to avoid NULL deref
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused
KVM: RISC-V: Use kvm_vcpu.srcu_idx, drop RISC-V's unnecessary copy
KVM: x86: Don't re-acquire SRCU lock in complete_emulated_io()
RISC-V: KVM: Restrict the extensions that can be disabled
RISC-V: KVM: Remove 's' & 'u' as valid ISA extension
Thomas Richter [Wed, 20 Apr 2022 06:29:21 +0000 (08:29 +0200)]
perf test: Fix error message for test case 71 on s390, where it is not supported
Test case 71 'Convert perf time to TSC' is not supported on s390.
Subtest 71.1 is skipped with the correct message, but subtest 71.2 is
not skipped and fails.
The root cause is function evlist__open() called from
test__perf_time_to_tsc(). evlist__open() returns -ENOENT because the
event cycles:u is not supported by the selected PMU, for example
platform s390 on z/VM or an x86_64 virtual machine.
The PMU driver returns -ENOENT in this case. This error is leads to the
failure.
Fix this by returning TEST_SKIP on -ENOENT.
Output before:
71: Convert perf time to TSC:
71.1: TSC support: Skip (This architecture does not support)
71.2: Perf time to TSC: FAILED!
Output after:
71: Convert perf time to TSC:
71.1: TSC support: Skip (This architecture does not support)
71.2: Perf time to TSC: Skip (perf_read_tsc_conversion is not supported)
This also happens on an x86_64 virtual machine:
# uname -m
x86_64
$ ./perf test -F 71
71: Convert perf time to TSC :
71.1: TSC support : Ok
71.2: Perf time to TSC : FAILED!
$
Committer testing:
Continues to work on x86_64:
$ perf test 71
71: Convert perf time to TSC :
71.1: TSC support : Ok
71.2: Perf time to TSC : Ok
$
Fixes: 3f95605f39b35ad8 ("perf test tsc: Fix error message when not supported") Signed-off-by: Thomas Richter <tmricht@linux.ibm.com> Acked-by: Sumanth Korikkar <sumanthk@linux.ibm.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Chengdong Li <chengdongli@tencent.com> Cc: chengdongli@tencent.com Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Link: https://lore.kernel.org/r/20220420062921.1211825-1-tmricht@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Leo Yan [Thu, 14 Apr 2022 12:32:01 +0000 (20:32 +0800)]
perf report: Set PERF_SAMPLE_DATA_SRC bit for Arm SPE event
Since commit 2fc3249501090d83 ("perf report: Bail out --mem-mode if mem
info is not available") "perf mem report" and "perf report --mem-mode"
don't report result if the PERF_SAMPLE_DATA_SRC bit is missed in sample
type.
The commit 32eb340c44d20894 ("perf: arm-spe: Fix perf report
--mem-mode") partially fixes the issue. It adds PERF_SAMPLE_DATA_SRC
bit for Arm SPE event, this allows the perf data file generated by
kernel v5.18-rc1 or later version can be reported properly.
On the other hand, perf tool still fails to be backward compatibility
for a data file recorded by an older version's perf which contains Arm
SPE trace data. This patch is a workaround in reporting phase, when
detects ARM SPE PMU event and without PERF_SAMPLE_DATA_SRC bit, it will
force to set the bit in the sample type and give a warning info.
Fixes: 2fc3249501090d83 ("perf report: Bail out --mem-mode if mem info is not available") Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Leo Yan <leo.yan@linaro.org> Tested-by: German Gomez <german.gomez@arm.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Link: https://lore.kernel.org/r/20220414123201.842754-1-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Leo Yan [Sun, 17 Apr 2022 11:48:37 +0000 (19:48 +0800)]
perf script: Always allow field 'data_src' for auxtrace
If use command 'perf script -F,+data_src' to dump memory samples with
Arm SPE trace data, it reports error:
# perf script -F,+data_src
Samples for 'dummy:u' event do not have DATA_SRC attribute set. Cannot print 'data_src' field.
This is because the 'dummy:u' event is absent DATA_SRC bit in its sample
type, so if a file contains AUX area tracing data then always allow
field 'data_src' to be selected as an option for perf script.
Fixes: 28128b5db06cbc2d ("perf arm-spe: Synthesize memory event") Signed-off-by: Leo Yan <leo.yan@linaro.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: German Gomez <german.gomez@arm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20220417114837.839896-1-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 962b3fc8b5a6 ("gpio: Restrict usage of GPIO chip irq members
before initialization") attempted to fix a race condition that lead to a
NULL pointer, but in the process caused a regression for _AEI/_EVT
declared GPIOs.
This manifests in messages showing deferred probing while trying to
allocate IRQs like so:
amd_gpio AMDI0030:00: Failed to translate GPIO pin 0x0000 to IRQ, err -517
amd_gpio AMDI0030:00: Failed to translate GPIO pin 0x002C to IRQ, err -517
amd_gpio AMDI0030:00: Failed to translate GPIO pin 0x003D to IRQ, err -517
[ .. more of the same .. ]
The code for walking _AEI doesn't handle deferred probing and so this
leads to non-functional GPIO interrupts.
Fix this issue by moving the call to `acpi_gpiochip_request_interrupts`
to occur after gc->irc.initialized is set.
Merge tag 'riscv-for-linus-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes Palmer Dabbelt:
- A pair of build fixes for the recent cpuidle driver
- A fix for systems without sv57 that manifests as a crash
early in boot
* tag 'riscv-for-linus-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
RISC-V: cpuidle: fix Kconfig select for RISCV_SBI_CPUIDLE
RISC-V: mm: Fix set_satp_mode() for platform not having Sv57
cpuidle: riscv: support non-SMP config
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"There's no real pattern to the fixes, but the main one fixes our
pmd_leaf() definition to resolve a NULL dereference on the migration
path.
- Fix PMU event validation in the absence of any event counters
- Fix allmodconfig build using clang in conjunction with binutils
- Fix definitions of pXd_leaf() to handle PROT_NONE entries
- More typo fixes"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: mm: fix p?d_leaf()
arm64: fix typos in comments
arm64: Improve HAVE_DYNAMIC_FTRACE_WITH_REGS selection for clang
arm_pmu: Validate single/group leader events
Miaoqian Lin [Wed, 20 Apr 2022 01:49:13 +0000 (01:49 +0000)]
arm/xen: Fix some refcount leaks
The of_find_compatible_node() function returns a node pointer with
refcount incremented, We should use of_node_put() on it when done
Add the missing of_node_put() to release the refcount.
Fixes: 0fa5c0e3b229 ("ARM: XEN: Move xen_early_init() before efi_init()") Fixes: 3fe625b0b84d ("arm/xen: Read extended regions from DT and init Xen resource") Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Reviewed-by: Stefano Stabellini <sstabellini@kernel.org> Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Merge tag 'xarray-5.18a' of git://git.infradead.org/users/willy/xarray
Pull xarray fixes from Matthew Wilcox:
"Syzbot found a nasty race between large page splitting and page
lookup. Details in the commit log, but fortunately it has a reliable
reproducer. I thought it better to send this one to you straight away.
Also fix the test suite build for kmem_cache_alloc_lru()"
* tag 'xarray-5.18a' of git://git.infradead.org/users/willy/xarray:
XArray: Disallow sibling entries of nodes
tools: Add kmem_cache_alloc_lru()
Merge tag '5.18-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Four fixes, two of them for stable:
- fcollapse fix
- reconnect lock fix
- DFS oops fix
- minor cleanup patch"
* tag '5.18-rc3-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: destage any unwritten data to the server before calling copychunk_write
cifs: use correct lock type in cifs_reconnect()
cifs: fix NULL ptr dereference in refresh_mounts()
cifs: Use kzalloc instead of kmalloc/memset
Merge tag 'fs.fixes.v5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull mount_setattr fix from Christian Brauner:
"The recent cleanup in ab2673ef1eec ("mount_setattr(): clean the
control flow and calling conventions") switched the mount attribute
codepaths from do-while to for loops as they are more idiomatic when
walking mounts.
However, we did originally choose do-while constructs because if we
request a mount or mount tree to be made read-only we need to hold
writers in the following way: The mount attribute code will grab
lock_mount_hash() and then call mnt_hold_writers() which will
_unconditionally_ set MNT_WRITE_HOLD on the mount.
Any callers that need write access have to call mnt_want_write(). They
will immediately see that MNT_WRITE_HOLD is set on the mount and the
caller will then either spin (on non-preempt-rt) or wait on
lock_mount_hash() (on preempt-rt).
The fact that MNT_WRITE_HOLD is set unconditionally means that once
mnt_hold_writers() returns we need to _always_ pair it with
mnt_unhold_writers() in both the failure and success paths.
The do-while constructs did take care of this. But Al's change to a
for loop in the failure path stops on the first mount we failed to
change mount attributes _without_ going into the loop to call
mnt_unhold_writers().
This in turn means that once we failed to make a mount read-only via
mount_setattr() - i.e. there are already writers on that mount - we
will block any writers indefinitely. Fix this by ensuring that the for
loop always unsets MNT_WRITE_HOLD including the first mount we failed
to change to read-only. Also sprinkle a few comments into the cleanup
code to remind people about what is happening including myself. After
all, I didn't catch it during review.
This is only relevant on mainline and was reported by syzbot. Details
about the syzbot reports are all in the commit message"
* tag 'fs.fixes.v5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
fs: unset MNT_WRITE_HOLD on failure
Merge tag 'sound-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"At this time, the majority of changes are for pending ASoC fixes while
a few usual HD-audio and USB-audio quirks are found.
Almost all patches are small device-specific fixes, and nothing
worrisome stands out, so far"
* tag 'sound-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound: (37 commits)
ALSA: hda/realtek: Add quirk for Clevo NP70PNP
ALSA: hda: intel-dsp-config: Add RaptorLake PCI IDs
ALSA: hda/realtek: Enable mute/micmute LEDs and limit mic boost on EliteBook 845/865 G9
ALSA: usb-audio: Clear MIDI port active flag after draining
ALSA: usb-audio: add mapping for MSI MAG X570S Torpedo MAX.
ALSA: hda/i915: Fix one too many pci_dev_put()
ALSA: hda/hdmi: add HDMI codec VID for Raptorlake-P
ALSA: hda/hdmi: fix warning about PCM count when used with SOF
sound/oss/dmasound: fix 'dmasound_setup' defined but not used
firmware: cs_dsp: Fix overrun of unterminated control name string
ASoC: codecs: Fix an error handling path in (rx|tx|va)_macro_probe()
ASoC: Intel: sof_es8336: Add a quirk for Huawei Matebook D15
ASoC: Intel: sof_es8336: add a quirk for headset at mic1 port
ASoC: Intel: sof_es8336: support a separate gpio to control headphone
ASoC: Intel: sof_es8336: simplify speaker gpio naming
ASoC: wm8731: Disable the regulator when probing fails
ASoC: Intel: soc-acpi: correct device endpoints for max98373
ASoC: codecs: wcd934x: do not switch off SIDO Buck when codec is in use
ASoC: SOF: topology: Fix memory leak in sof_control_load()
ASoC: SOF: topology: cleanup dailinks on widget unload
...
There is a race between xas_split() and xas_load() which can result in
the wrong page being returned, and thus data corruption. Fortunately,
it's hard to hit (syzbot took three months to find it) and often guarded
with VM_BUG_ON().
The anatomy of this race is:
thread A thread B
order-9 page is stored at index 0x200
lookup of page at index 0x274
page split starts
load of sibling entry at offset 9
stores nodes at offsets 8-15
load of entry at offset 8
The entry at offset 8 turns out to be a node, and so we descend into it,
and load the page at index 0x234 instead of 0x274. This is hard to fix
on the split side; we could replace the entire node that contains the
order-9 page instead of replacing the eight entries. Fixing it on
the lookup side is easier; just disallow sibling entries that point
to nodes. This cannot ever be a useful thing as the descent would not
know the correct offset to use within the new node.
The test suite continues to pass, but I have not added a new test for
this bug.
Reported-by: syzbot+cf4cf13056f85dec2c40@syzkaller.appspotmail.com Tested-by: syzbot+cf4cf13056f85dec2c40@syzkaller.appspotmail.com Fixes: b630484fb760 ("mm: Use multi-index entries in the page cache") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Turn kmem_cache_alloc() into a wrapper around kmem_cache_alloc_lru().
Fixes: da59ab7be2cc ("xarray: use kmem_cache_alloc_lru to allocate xa_node") Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reported-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reported-by: Li Wang <liwang@redhat.com>
Subsystems affected by this patch series: mm (memory-failure, memcg,
userfaultfd, hugetlbfs, mremap, oom-kill, kasan, hmm), and kcov"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove()
kcov: don't generate a warning on vm_insert_page()'s failure
MAINTAINERS: add Vincenzo Frascino to KASAN reviewers
oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup
selftest/vm: add skip support to mremap_test
selftest/vm: support xfail in mremap_test
selftest/vm: verify remap destination address in mremap_test
selftest/vm: verify mmap addr in mremap_test
mm, hugetlb: allow for "high" userspace addresses
userfaultfd: mark uffd_wp regardless of VM_WRITE flag
memcg: sync flush only if periodic flush is delayed
mm/memory-failure.c: skip huge_zero_page in memory_failure()
mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()
Nicholas Piggin [Fri, 22 Apr 2022 06:01:05 +0000 (16:01 +1000)]
mm/vmalloc: huge vmalloc backing pages should be split rather than compound
Huge vmalloc higher-order backing pages were allocated with __GFP_COMP
in order to allow the sub-pages to be refcounted by callers such as
"remap_vmalloc_page [sic]" (remap_vmalloc_range).
However a similar problem exists for other struct page fields callers
use, for example fb_deferred_io_fault() takes a vmalloc'ed page and
not only refcounts it but uses ->lru, ->mapping, ->index.
This is not compatible with compound sub-pages, and can cause bad page
state issues like
The correct approach is to use split high-order pages for the huge
vmalloc backing. These allow callers to treat them in exactly the same
way as individually-allocated order-0 pages.
Link: https://lore.kernel.org/all/14444103-d51b-0fb3-ee63-c3f182f0b546@molgen.mpg.de/ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Cc: Paul Menzel <pmenzel@molgen.mpg.de> Cc: Song Liu <songliubraving@fb.com> Cc: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Muchun Song [Fri, 22 Apr 2022 06:00:33 +0000 (14:00 +0800)]
arm64: mm: fix p?d_leaf()
The pmd_leaf() is used to test a leaf mapped PMD, however, it misses
the PROT_NONE mapped PMD on arm64. Fix it. A real world issue [1]
caused by this was reported by Qian Cai. Also fix pud_leaf().
Merge tag 'drm-fixes-2022-04-22' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"Extra quiet after Easter, only have minor i915 and msm pulls. However
I haven't seen a PR from our misc tree in a little while, I've cc'ed
all the suspects. Once that unblocks I expect a bit larger bunch of
patches to arrive.
Otherwise as I said, one msm revert and two i915 fixes.
msm:
- revert iommu change that broke some platforms.
i915:
- Unset enable_psr2_sel_fetch if PSR2 detection fails
- Fix to detect when VRR is turned off from panel settings"
* tag 'drm-fixes-2022-04-22' of git://anongit.freedesktop.org/drm/drm:
drm/i915/display/psr: Unset enable_psr2_sel_fetch if other checks in intel_psr2_config_valid() fails
drm/msm: Revert "drm/msm: Stop using iommu_present()"
drm/i915/display/vrr: Reset VRR capable property on a long hpd
mm/mmu_notifier.c: fix race in mmu_interval_notifier_remove()
In some cases it is possible for mmu_interval_notifier_remove() to race
with mn_tree_inv_end() allowing it to return while the notifier data
structure is still in use. Consider the following sequence:
As the wait_event() condition is true it will return immediately. This
can lead to use-after-free type errors if the caller frees the data
structure containing the interval notifier subscription while it is
still on a deferred list. Fix this by taking the appropriate lock when
reading invalidate_seq to ensure proper synchronisation.
I observed this whilst running stress testing during some development.
You do have to be pretty unlucky, but it leads to the usual problems of
use-after-free (memory corruption, kernel crash, difficult to diagnose
WARN_ON, etc).
Link: https://lkml.kernel.org/r/20220420043734.476348-1-apopple@nvidia.com Fixes: c8673ef63452 ("mm/mmu_notifier: add an interval tree notifier") Signed-off-by: Alistair Popple <apopple@nvidia.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Christian König <christian.koenig@amd.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Aleksandr Nogikh [Thu, 21 Apr 2022 23:36:07 +0000 (16:36 -0700)]
kcov: don't generate a warning on vm_insert_page()'s failure
vm_insert_page()'s failure is not an unexpected condition, so don't do
WARN_ONCE() in such a case.
Instead, print a kernel message and just return an error code.
This flaw has been reported under an OOM condition by sysbot [1].
The message is mainly for the benefit of the test log, in this case the
fuzzer's log so that humans inspecting the log can figure out what was
going on. KCOV is a testing tool, so I think being a little more chatty
when KCOV unexpectedly is about to fail will save someone debugging
time.
We don't want the WARN, because it's not a kernel bug that syzbot should
report, and failure can happen if the fuzzer tries hard enough (as
above).
Link: https://lkml.kernel.org/r/Ylkr2xrVbhQYwNLf@elver.google.com Link: https://lkml.kernel.org/r/20220401182512.249282-1-nogikh@google.com Fixes: f7bc6f9e3e0f ("kcov: properly handle subsequent mmap calls"), Signed-off-by: Aleksandr Nogikh <nogikh@google.com> Acked-by: Marco Elver <elver@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Taras Madan <tarasmadan@google.com> Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
oom_kill.c: futex: delay the OOM reaper to allow time for proper futex cleanup
The pthread struct is allocated on PRIVATE|ANONYMOUS memory [1] which
can be targeted by the oom reaper. This mapping is used to store the
futex robust list head; the kernel does not keep a copy of the robust
list and instead references a userspace address to maintain the
robustness during a process death.
A race can occur between exit_mm and the oom reaper that allows the oom
reaper to free the memory of the futex robust list before the exit path
has handled the futex death:
selftest/vm: verify remap destination address in mremap_test
Because mremap does not have a MAP_FIXED_NOREPLACE flag, it can destroy
existing mappings. This causes a segfault when regions such as text are
remapped and the permissions are changed.
Verify the requested mremap destination address does not overlap any
existing mappings by using mmap's MAP_FIXED_NOREPLACE flag. Keep
incrementing the destination address until a valid mapping is found or
fail the current test once the max address is reached.
Avoid calling mmap with requested addresses that are less than the
system's mmap_min_addr. When run as root, mmap returns EACCES when
trying to map addresses < mmap_min_addr. This is not one of the error
codes for the condition to retry the mmap in the test.
Rather than arbitrarily retrying on EACCES, don't attempt an mmap until
addr > vm.mmap_min_addr.
Add a munmap call after an alignment check as the mappings are retained
after the retry and can reach the vm.max_map_count sysctl.
This is a fix for commit fb89424b6dc8 ("mm: mmap: Allow for "high"
userspace addresses") for hugetlb.
This patch adds support for "high" userspace addresses that are
optionally supported on the system and have to be requested via a hint
mechanism ("high" addr parameter to mmap).
Architectures such as powerpc and x86 achieve this by making changes to
their architectural versions of hugetlb_get_unmapped_area() function.
However, arm64 uses the generic version of that function.
So take into account arch_get_mmap_base() and arch_get_mmap_end() in
hugetlb_get_unmapped_area(). To allow that, move those two macros out
of mm/mmap.c into include/linux/sched/mm.h
If these macros are not defined in architectural code then they default
to (TASK_SIZE) and (base) so should not introduce any behavioural
changes to architectures that do not define them.
For the time being, only ARM64 is affected by this change.
Catalin (ARM64) said
"We should have fixed hugetlb_get_unmapped_area() as well when we added
support for 52-bit VA. The reason for commit fb89424b6dc8 was to
prevent normal mmap() from returning addresses above 48-bit by default
as some user-space had hard assumptions about this.
It's a slight ABI change if you do this for hugetlb_get_unmapped_area()
but I doubt anyone would notice. It's more likely that the current
behaviour would cause issues, so I'd rather have them consistent.
Basically when arm64 gained support for 52-bit addresses we did not
want user-space calling mmap() to suddenly get such high addresses,
otherwise we could have inadvertently broken some programs (similar
behaviour to x86 here). Hence we added commit fb89424b6dc8. But we
missed hugetlbfs which could still get such high mmap() addresses. So
in theory that's a potential regression that should have bee addressed
at the same time as commit fb89424b6dc8 (and before arm64 enabled
52-bit addresses)"
Link: https://lkml.kernel.org/r/ab847b6edb197bffdfe189e70fb4ac76bfe79e0d.1650033747.git.christophe.leroy@csgroup.eu Fixes: fb89424b6dc8 ("mm: mmap: Allow for "high" userspace addresses") Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Steve Capper <steve.capper@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> [5.0.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Thu, 21 Apr 2022 23:35:43 +0000 (16:35 -0700)]
userfaultfd: mark uffd_wp regardless of VM_WRITE flag
When a PTE is set by UFFD operations such as UFFDIO_COPY, the PTE is
currently only marked as write-protected if the VMA has VM_WRITE flag
set. This seems incorrect or at least would be unexpected by the users.
Consider the following sequence of operations that are being performed
on a certain page:
At this point the user would expect to still get UFFD notification when
the page is accessed for write, but the user would not get one, since
the PTE was not marked as UFFD_WP during UFFDIO_COPY.
Fix it by always marking PTEs as UFFD_WP regardless on the
write-permission in the VMA flags.
Link: https://lkml.kernel.org/r/20220217211602.2769-1-namit@vmware.com Fixes: f50cc3c6f0d5 ("userfaultfd: wp: apply _PAGE_UFFD_WP bit") Signed-off-by: Nadav Amit <namit@vmware.com> Acked-by: Peter Xu <peterx@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: sync flush only if periodic flush is delayed
Daniel Dao has reported [1] a regression on workloads that may trigger a
lot of refaults (anon and file). The underlying issue is that flushing
rstat is expensive. Although rstat flush are batched with (nr_cpus *
MEMCG_BATCH) stat updates, it seems like there are workloads which
genuinely do stat updates larger than batch value within short amount of
time. Since the rstat flush can happen in the performance critical
codepaths like page faults, such workload can suffer greatly.
This patch fixes this regression by making the rstat flushing
conditional in the performance critical codepaths. More specifically,
the kernel relies on the async periodic rstat flusher to flush the stats
and only if the periodic flusher is delayed by more than twice the
amount of its normal time window then the kernel allows rstat flushing
from the performance critical codepaths.
Now the question: what are the side-effects of this change? The worst
that can happen is the refault codepath will see 4sec old lruvec stats
and may cause false (or missed) activations of the refaulted page which
may under-or-overestimate the workingset size. Though that is not very
concerning as the kernel can already miss or do false activations.
There are two more codepaths whose flushing behavior is not changed by
this patch and we may need to come to them in future. One is the
writeback stats used by dirty throttling and second is the deactivation
heuristic in the reclaim. For now keeping an eye on them and if there
is report of regression due to these codepaths, we will reevaluate then.
Link: https://lore.kernel.org/all/CA+wXwBSyO87ZX5PVwdHm-=dBjZYECGmfnydUicUyrQqndgX2MQ@mail.gmail.com Link: https://lkml.kernel.org/r/20220304184040.1304781-1-shakeelb@google.com Fixes: 4cd61058cf95 ("memcg: flush lruvec stats in the refault") Signed-off-by: Shakeel Butt <shakeelb@google.com> Reported-by: Daniel Dao <dqminh@cloudflare.com> Tested-by: Ivan Babrou <ivan@cloudflare.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Frank Hofmann <fhofmann@cloudflare.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm/hwpoison: fix race between hugetlb free/demotion and memory_failure_hugetlb()
There is a race condition between memory_failure_hugetlb() and hugetlb
free/demotion, which causes setting PageHWPoison flag on the wrong page.
The one simple result is that wrong processes can be killed, but another
(more serious) one is that the actual error is left unhandled, so no one
prevents later access to it, and that might lead to more serious results
like consuming corrupted data.
Think about the below race window:
CPU 1 CPU 2
memory_failure_hugetlb
struct page *head = compound_head(p);
hugetlb page might be freed to
buddy, or even changed to another
compound page.
get_hwpoison_page -- page is not what we want now...
The current code first does prechecks roughly and then reconfirms after
taking refcount, but it's found that it makes code overly complicated,
so move the prechecks in a single hugetlb_lock range.
A newly introduced function, try_memory_failure_hugetlb(), always takes
hugetlb_lock (even for non-hugetlb pages). That can be improved, but
memory_failure() is rare in principle, so should not be a big problem.
Link: https://lkml.kernel.org/r/20220408135323.1559401-2-naoya.horiguchi@linux.dev Fixes: 5d249261ac3b ("mm: hwpoison: introduce memory_failure_hugetlb()") Signed-off-by: Naoya Horiguchi <naoya.horiguchi@nec.com> Reported-by: Mike Kravetz <mike.kravetz@oracle.com> Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zheyu Ma [Thu, 21 Apr 2022 01:39:20 +0000 (09:39 +0800)]
ata: pata_marvell: Check the 'bmdma_addr' beforing reading
Before detecting the cable type on the dma bar, the driver should check
whether the 'bmdma_addr' is zero, which means the adapter does not
support DMA, otherwise we will get the following error:
Merge tag 'dmaengine-fix-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine
Pull dmaengine fixes from Vinod Koul:
"A bunch of driver fixes:
- idxd device RO checks and device cleanup
- dw-edma unaligned access and alignment
- qcom: missing minItems in binding
- mediatek pm usage fix
- imx init script"
* tag 'dmaengine-fix-5.18' of git://git.kernel.org/pub/scm/linux/kernel/git/vkoul/dmaengine:
dt-bindings: dmaengine: qcom: gpi: Add minItems for interrupts
dmaengine: idxd: skip clearing device context when device is read-only
dmaengine: idxd: add RO check for wq max_transfer_size write
dmaengine: idxd: add RO check for wq max_batch_size write
dmaengine: idxd: fix retry value to be constant for duration of function call
dmaengine: idxd: match type for retries var in idxd_enqcmds()
dmaengine: dw-edma: Fix inconsistent indenting
dmaengine: dw-edma: Fix unaligned 64bit access
dmaengine: mediatek:Fix PM usage reference leak of mtk_uart_apdma_alloc_chan_resources
dmaengine: imx-sdma: Fix error checking in sdma_event_remap
dma: at_xdmac: fix a missing check on list iterator
dmaengine: imx-sdma: fix init of uart scripts
dmaengine: idxd: fix device cleanup on disable
RISC-V: mm: Fix set_satp_mode() for platform not having Sv57
When Sv57 is not available the satp.MODE test in set_satp_mode() will
fail and lead to pgdir re-programming for Sv48. The pgdir re-programming
will fail as well due to pre-existing pgdir entry used for Sv57 and as
a result kernel fails to boot on RISC-V platform not having Sv57.
To fix above issue, we should clear the pgdir memory in set_satp_mode()
before re-programming.
Populating memory : 0.684014577s
Writing to populated memory : 0.006230175s
Reading from populated memory : 0.004557805s
==== Test Assertion Failure ====
lib/kvm_util.c:1411: false
pid=125806 tid=125809 errno=4 - Interrupted system call
1 0x0000000000402f7c: addr_gpa2hva at kvm_util.c:1411
2 (inlined by) addr_gpa2hva at kvm_util.c:1405
3 0x0000000000401f52: lookup_pfn at access_tracking_perf_test.c:98
4 (inlined by) mark_vcpu_memory_idle at access_tracking_perf_test.c:152
5 (inlined by) vcpu_thread_main at access_tracking_perf_test.c:232
6 0x00007fefe9ff81ce: ?? ??:0
7 0x00007fefe9c64d82: ?? ??:0
No vm physical memory at 0xffbffff000
I can easily reproduce it with a Intel(R) Xeon(R) CPU E5-2630 with 46 bits
PA.
It turns out that the address translation for clearing idle page tracking
returned a wrong result; addr_gva2gpa()'s last step, which is based on
"pte[index[0]].pfn", did the calculation with 40 bits length and the
high 12 bits got truncated. In above case the GPA address to be returned
should be 0x3fffbffff000 for GVA 0xc0000000, but it got truncated into
0xffbffff000 and the subsequent gpa2hva lookup failed.
The width of operations on bit fields greater than 32-bit is
implementation defined, and differs between GCC (which uses the bitfield
precision) and clang (which uses 64-bit arithmetic), so this is a
potential minefield. Remove the bit fields and using manual masking
instead.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2075036 Reported-by: Nana Liu <nanliu@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Peter Xu <peterx@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: SEV: add cache flush to solve SEV cache incoherency issues
Flush the CPU caches when memory is reclaimed from an SEV guest (where
reclaim also includes it being unmapped from KVM's memslots). Due to lack
of coherency for SEV encrypted memory, failure to flush results in silent
data corruption if userspace is malicious/broken and doesn't ensure SEV
guest memory is properly pinned and unpinned.
Cache coherency is not enforced across the VM boundary in SEV (AMD APM
vol.2 Section 15.34.7). Confidential cachelines, generated by confidential
VM guests have to be explicitly flushed on the host side. If a memory page
containing dirty confidential cachelines was released by VM and reallocated
to another user, the cachelines may corrupt the new user at a later time.
KVM takes a shortcut by assuming all confidential memory remain pinned
until the end of VM lifetime. Therefore, KVM does not flush cache at
mmu_notifier invalidation events. Because of this incorrect assumption and
the lack of cache flushing, malicous userspace can crash the host kernel:
creating a malicious VM and continuously allocates/releases unpinned
confidential memory pages when the VM is running.
Add cache flush operations to mmu_notifier operations to ensure that any
physical memory leaving the guest VM get flushed. In particular, hook
mmu_notifier_invalidate_range_start and mmu_notifier_release events and
flush cache accordingly. The hook after releasing the mmu lock to avoid
contention with other vCPUs.
Cc: stable@vger.kernel.org Suggested-by: Sean Christpherson <seanjc@google.com> Reported-by: Mingwei Zhang <mizhang@google.com> Signed-off-by: Mingwei Zhang <mizhang@google.com>
Message-Id: <20220421031407.2516575-4-mizhang@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Merge tag 'net-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Paolo Abeni:
"Including fixes from xfrm and can.
Current release - regressions:
- rxrpc: restore removed timer deletion
Current release - new code bugs:
- gre: fix device lookup for l3mdev use-case
- xfrm: fix egress device lookup for l3mdev use-case
Previous releases - regressions:
- sched: cls_u32: fix netns refcount changes in u32_change()
- smc: fix sock leak when release after smc_shutdown()
- xfrm: limit skb_page_frag_refill use to a single page
- eth: atlantic: invert deep par in pm functions, preventing null
derefs
- eth: stmmac: use readl_poll_timeout_atomic() in atomic state
Previous releases - always broken:
- gre: fix skb_under_panic on xmit
- openvswitch: fix OOB access in reserve_sfa_size()
- dsa: hellcreek: calculate checksums in tagger
- eth: ice: fix crash in switchdev mode
- eth: igc:
- fix infinite loop in release_swfw_sync
- fix scheduling while atomic"
* tag 'net-5.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (37 commits)
drivers: net: hippi: Fix deadlock in rr_close()
selftests: mlxsw: vxlan_flooding_ipv6: Prevent flooding of unwanted packets
selftests: mlxsw: vxlan_flooding: Prevent flooding of unwanted packets
nfc: MAINTAINERS: add Bug entry
net: stmmac: Use readl_poll_timeout_atomic() in atomic state
doc/ip-sysctl: add bc_forwarding
netlink: reset network and mac headers in netlink_dump()
net: mscc: ocelot: fix broken IP multicast flooding
net: dsa: hellcreek: Calculate checksums in tagger
net: atlantic: invert deep par in pm functions, preventing null derefs
can: isotp: stop timeout monitoring when no first frame was sent
bonding: do not discard lowest hash bit for non layer3+4 hashing
net: lan966x: Make sure to release ptp interrupt
ipv6: make ip6_rt_gc_expire an atomic_t
net: Handle l3mdev in ip_tunnel_init_flow
l3mdev: l3mdev_master_upper_ifindex_by_index_rcu should be using netdev_master_upper_dev_get_rcu
net/sched: cls_u32: fix possible leak in u32_init_knode()
net/sched: cls_u32: fix netns refcount changes in u32_change()
powerpc: Update MAINTAINERS for ibmvnic and VAS
net: restore alpha order to Ethernet devices in config
...
Above issue may happen as follows:
write truncate kjournald2
generic_perform_write
ext4_write_begin
ext4_walk_page_buffers
do_journal_get_write_access ->add BJ_Reserved list
ext4_journalled_write_end
ext4_walk_page_buffers
write_end_fn
ext4_handle_dirty_metadata
***************JBD2 ABORT**************
jbd2_journal_dirty_metadata
-> return -EROFS, jh in reserved_list
jbd2_journal_commit_transaction
while (commit_transaction->t_reserved_list)
jh = commit_transaction->t_reserved_list;
truncate_pagecache_range
do_invalidatepage
ext4_journalled_invalidatepage
jbd2_journal_invalidatepage
journal_unmap_buffer
__dispose_buffer
__jbd2_journal_unfile_buffer
jbd2_journal_put_journal_head ->put last ref_count
__journal_remove_journal_head
bh->b_private = NULL;
jh->b_bh = NULL;
jbd2_journal_refile_buffer(journal, jh);
bh = jh2bh(jh);
->bh is NULL, later will trigger null-ptr-deref
journal_free_journal_head(jh);
After commit 2a629849c6e3, we no longer hold the j_state_lock while
iterating over the list of reserved handles in
jbd2_journal_commit_transaction(). This potentially allows the
journal_head to be freed by journal_unmap_buffer while the commit
codepath is also trying to free the BJ_Reserved buffers. Keeping
j_state_lock held while trying extends hold time of the lock
minimally, and solves this issue.
Fixes: 2a629849c6e3("jbd2: avoid long hold times of j_state_lock while committing a transaction") Signed-off-by: Ye Bin <yebin10@huawei.com> Reviewed-by: Jan Kara <jack@suse.cz> Link: https://lore.kernel.org/r/20220317142137.1821590-1-yebin10@huawei.com Signed-off-by: Theodore Ts'o <tytso@mit.edu>
KVM: SVM: Flush when freeing encrypted pages even on SME_COHERENT CPUs
Use clflush_cache_range() to flush the confidential memory when
SME_COHERENT is supported in AMD CPU. Cache flush is still needed since
SME_COHERENT only support cache invalidation at CPU side. All confidential
cache lines are still incoherent with DMA devices.
Cc: stable@vger.kerel.org Fixes: 02d085e11c00 ("KVM: SVM: Add support for the SEV-ES VMSA") Reviewed-by: Sean Christopherson <seanjc@google.com> Signed-off-by: Mingwei Zhang <mizhang@google.com>
Message-Id: <20220421031407.2516575-3-mizhang@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: SVM: Simplify and harden helper to flush SEV guest page(s)
Rework sev_flush_guest_memory() to explicitly handle only a single page,
and harden it to fall back to WBINVD if VM_PAGE_FLUSH fails. Per-page
flushing is currently used only to flush the VMSA, and in its current
form, the helper is completely broken with respect to flushing actual
guest memory, i.e. won't work correctly for an arbitrary memory range.
VM_PAGE_FLUSH takes a host virtual address, and is subject to normal page
walks, i.e. will fault if the address is not present in the host page
tables or does not have the correct permissions. Current AMD CPUs also
do not honor SMAP overrides (undocumented in kernel versions of the APM),
so passing in a userspace address is completely out of the question. In
other words, KVM would need to manually walk the host page tables to get
the pfn, ensure the pfn is stable, and then use the direct map to invoke
VM_PAGE_FLUSH. And the latter might not even work, e.g. if userspace is
particularly evil/clever and backs the guest with Secret Memory (which
unmaps memory from the direct map).
Signed-off-by: Sean Christopherson <seanjc@google.com> Fixes: 02d085e11c00 ("KVM: SVM: Add support for the SEV-ES VMSA") Reported-by: Mingwei Zhang <mizhang@google.com> Cc: stable@vger.kernel.org Signed-off-by: Mingwei Zhang <mizhang@google.com>
Message-Id: <20220421031407.2516575-2-mizhang@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Like Xu [Sat, 9 Apr 2022 01:52:26 +0000 (09:52 +0800)]
KVM: x86/pmu: Update AMD PMC sample period to fix guest NMI-watchdog
NMI-watchdog is one of the favorite features of kernel developers,
but it does not work in AMD guest even with vPMU enabled and worse,
the system misrepresents this capability via /proc.
This is a PMC emulation error. KVM does not pass the latest valid
value to perf_event in time when guest NMI-watchdog is running, thus
the perf_event corresponding to the watchdog counter will enter the
old state at some point after the first guest NMI injection, forcing
the hardware register PMC0 to be constantly written to 0x800000000001.
Meanwhile, the running counter should accurately reflect its new value
based on the latest coordinated pmc->counter (from vPMC's point of view)
rather than the value written directly by the guest.
Fixes: 44ab0217af7f ("KVM: x86: Adjust counter sample period after a wrmsr") Reported-by: Dongli Cao <caodongli@kingsoft.com> Signed-off-by: Like Xu <likexu@tencent.com> Reviewed-by: Yanan Wang <wangyanan55@huawei.com> Tested-by: Yanan Wang <wangyanan55@huawei.com> Reviewed-by: Jim Mattson <jmattson@google.com>
Message-Id: <20220409015226.38619-1-likexu@tencent.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Wanpeng Li [Mon, 18 Apr 2022 07:42:32 +0000 (00:42 -0700)]
x86/kvm: Preserve BSP MSR_KVM_POLL_CONTROL across suspend/resume
MSR_KVM_POLL_CONTROL is cleared on reset, thus reverting guests to
host-side polling after suspend/resume. Non-bootstrap CPUs are
restored correctly by the haltpoll driver because they are hot-unplugged
during suspend and hot-plugged during resume; however, the BSP
is not hotpluggable and remains in host-sde polling mode after
the guest resume. The makes the guest pay for the cost of vmexits
every time the guest enters idle.
Fix it by recording BSP's haltpoll state and resuming it during guest
resume.
Cc: Marcelo Tosatti <mtosatti@redhat.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1650267752-46796-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Skip KVM_GUESTDBG_BLOCKIRQ APICv update if APICv is disabled
Skip the APICv inhibit update for KVM_GUESTDBG_BLOCKIRQ if APICv is
disabled at the module level to avoid having to acquire the mutex and
potentially process all vCPUs. The DISABLE inhibit will (barring bugs)
never be lifted, so piling on more inhibits is unnecessary.
Fixes: 4fe180dc1b9a ("KVM: x86: inhibit APICv when KVM_GUESTDBG_BLOCKIRQ active") Cc: Maxim Levitsky <mlevitsk@redhat.com> Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220420013732.3308816-5-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Pend KVM_REQ_APICV_UPDATE during vCPU creation to fix a race
Make a KVM_REQ_APICV_UPDATE request when creating a vCPU with an
in-kernel local APIC and APICv enabled at the module level. Consuming
kvm_apicv_activated() and stuffing vcpu->arch.apicv_active directly can
race with __kvm_set_or_clear_apicv_inhibit(), as vCPU creation happens
before the vCPU is fully onlined, i.e. it won't get the request made to
"all" vCPUs. If APICv is globally inhibited between setting apicv_active
and onlining the vCPU, the vCPU will end up running with APICv enabled
and trigger KVM's sanity check.
Mark APICv as active during vCPU creation if APICv is enabled at the
module level, both to be optimistic about it's final state, e.g. to avoid
additional VMWRITEs on VMX, and because there are likely bugs lurking
since KVM checks apicv_active in multiple vCPU creation paths. While
keeping the current behavior of consuming kvm_apicv_activated() is
arguably safer from a regression perspective, force apicv_active so that
vCPU creation runs with deterministic state and so that if there are bugs,
they are found sooner than later, i.e. not when some crazy race condition
is hit.
KVM: nVMX: Defer APICv updates while L2 is active until L1 is active
Defer APICv updates that occur while L2 is active until nested VM-Exit,
i.e. until L1 regains control. vmx_refresh_apicv_exec_ctrl() assumes L1
is active and (a) stomps all over vmcs02 and (b) neglects to ever updated
vmcs01. E.g. if vmcs12 doesn't enable the TPR shadow for L2 (and thus no
APICv controls), L1 performs nested VM-Enter APICv inhibited, and APICv
becomes unhibited while L2 is active, KVM will set various APICv controls
in vmcs02 and trigger a failed VM-Entry. The kicker is that, unless
running with nested_early_check=1, KVM blames L1 and chaos ensues.
In all cases, ignoring vmcs02 and always deferring the inhibition change
to vmcs01 is correct (or at least acceptable). The ABSENT and DISABLE
inhibitions cannot truly change while L2 is active (see below).
IRQ_BLOCKING can change, but it is firmly a best effort debug feature.
Furthermore, only L2's APIC is accelerated/virtualized to the full extent
possible, e.g. even if L1 passes through its APIC to L2, normal MMIO/MSR
interception will apply to the virtual APIC managed by KVM.
The exception is the SELF_IPI register when x2APIC is enabled, but that's
an acceptable hole.
Lastly, Hyper-V's Auto EOI can technically be toggled if L1 exposes the
MSRs to L2, but for that to work in any sane capacity, L1 would need to
pass through IRQs to L2 as well, and IRQs must be intercepted to enable
virtual interrupt delivery. I.e. exposing Auto EOI to L2 and enabling
VID for L2 are, for all intents and purposes, mutually exclusive.
Lack of dynamic toggling is also why this scenario is all but impossible
to encounter in KVM's current form. But a future patch will pend an
APICv update request _during_ vCPU creation to plug a race where a vCPU
that's being created doesn't get included in the "all vCPUs request"
because it's not yet visible to other vCPUs. If userspaces restores L2
after VM creation (hello, KVM selftests), the first KVM_RUN will occur
while L2 is active and thus service the APICv update request made during
VM creation.
Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220420013732.3308816-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Tag APICv DISABLE inhibit, not ABSENT, if APICv is disabled
Set the DISABLE inhibit, not the ABSENT inhibit, if APICv is disabled via
module param. A recent refactoring to add a wrapper for setting/clearing
inhibits unintentionally changed the flag, probably due to a copy+paste
goof.
Fixes: bc691fca4628 ("KVM: x86: Trace all APICv inhibit changes and capture overall status") Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220420013732.3308816-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: Initialize debugfs_dentry when a VM is created to avoid NULL deref
Initialize debugfs_entry to its semi-magical -ENOENT value when the VM
is created. KVM's teardown when VM creation fails is kludgy and calls
kvm_uevent_notify_change() and kvm_destroy_vm_debugfs() even if KVM never
attempted kvm_create_vm_debugfs(). Because debugfs_entry is zero
initialized, the IS_ERR() checks pass and KVM derefs a NULL pointer.
Fixes: c3d82a65b83c ("KVM: Don't create VM debugfs files outside of the VM directory") Cc: stable@vger.kernel.org Cc: Marc Zyngier <maz@kernel.org> Cc: Oliver Upton <oupton@google.com> Reported-by: syzbot+df6fbbd2ee39f21289ef@syzkaller.appspotmail.com Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Oliver Upton <oupton@google.com>
Message-Id: <20220415004622.2207751-1-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused
Add wrappers to acquire/release KVM's SRCU lock when stashing the index
in vcpu->src_idx, along with rudimentary detection of illegal usage,
e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the
SRCU index is (currently) either 0 or 1, illegal nesting bugs can go
unnoticed for quite some time and only cause problems when the nested
lock happens to get a different index.
Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will
likely yell so loudly that it will bring the kernel to its knees.
Signed-off-by: Sean Christopherson <seanjc@google.com> Tested-by: Fabiano Rosas <farosas@linux.ibm.com>
Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: RISC-V: Use kvm_vcpu.srcu_idx, drop RISC-V's unnecessary copy
Use the generic kvm_vcpu's srcu_idx instead of using an indentical field
in RISC-V's version of kvm_vcpu_arch. Generic KVM very intentionally
does not touch vcpu->srcu_idx, i.e. there's zero chance of running afoul
of common code.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220415004343.2203171-3-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM: x86: Don't re-acquire SRCU lock in complete_emulated_io()
Don't re-acquire SRCU in complete_emulated_io() now that KVM acquires the
lock in kvm_arch_vcpu_ioctl_run(). More importantly, don't overwrite
vcpu->srcu_idx. If the index acquired by complete_emulated_io() differs
from the one acquired by kvm_arch_vcpu_ioctl_run(), KVM will effectively
leak a lock and hang if/when synchronize_srcu() is invoked for the
relevant grace period.
Fixes: a7b7f3d93b37 ("KVM: x86: pull kvm->srcu read-side to kvm_arch_vcpu_ioctl_run") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <seanjc@google.com> Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220415004343.2203171-2-seanjc@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
After mnt_hold_writers() has been called we will always have set MNT_WRITE_HOLD
and consequently we always need to pair mnt_hold_writers() with
mnt_unhold_writers(). After the recent cleanup in [1] where Al switched from a
do-while to a for loop the cleanup currently fails to unset MNT_WRITE_HOLD for
the first mount that was changed. Fix this and make sure that the first mount
will be cleaned up and add some comments to make it more obvious.
The "read_bhrb" global symbol is only called under CONFIG_PPC64 of
arch/powerpc/perf/core-book3s.c but it is compiled for both 32 and 64 bit
anyway (and LLVM fails to link this on 32bit).
When scheduling a group of events, there are constraint checks done to
make sure all events can go in a group. Example, one of the criteria is
that events in a group cannot use the same PMC. But platform specific
PMU supports alternative event for some of the event codes. During
perf_event_open(), if any event group doesn't match constraint check
criteria, further lookup is done to find alternative event.
By current design, the array of alternatives events in PMU code is
expected to be sorted by column 0. This is because in
find_alternative() the return criteria is based on event code
comparison. ie. "event < ev_alt[i][0])". This optimisation is there
since find_alternative() can be called multiple times. In power10 PMU
code, the alternative event array is not sorted properly and hence there
is breakage in finding alternative event.
To work with existing logic, fix the alternative event array to be
sorted by column 0 for power10-pmu.c
Results:
In case where an alternative event is not chosen when we could, events
will be multiplexed. ie, time sliced where it could actually run
concurrently.
Example, in power10 PM_INST_CMPL_ALT(0x00002) has alternative event,
PM_INST_CMPL(0x500fa). Without the fix, if a group of events with PMC1
to PMC4 is used along with PM_INST_CMPL_ALT, it will be time sliced
since all programmable PMC's are consumed already. But with the fix,
when it picks alternative event on PMC5, all events will run
concurrently.
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