Firoz Khan [Mon, 17 Dec 2018 10:40:34 +0000 (16:10 +0530)]
powerpc: add system call table generation support
The system call tables are in different format in all
architecture and it will be difficult to manually add or
modify the system calls in the respective files. To make
it easy by keeping a script and which will generate the
uapi header and syscall table file. This change will also
help to unify the implementation across all architectures.
The system call table generation script is added in
syscalls directory which contain the script to generate
both uapi header file and system call table files.
The syscall.tbl file will be the input for the scripts.
syscall.tbl contains the list of available system calls
along with system call number and corresponding entry point.
Add a new system call in this architecture will be possible
by adding new entry in the syscall.tbl file.
Adding a new table entry consisting of:
- System call number.
- ABI.
- System call name.
- Entry point name.
- Compat entry name, if required.
syscallhdr.sh and syscalltbl.sh will generate uapi header-
unistd_32/64.h and syscall_table_32/64/c32/spu.h files
respectively. File syscall_table_32/64/c32/spu.h is incl-
uded by syscall.S - the real system call table. Both *.sh
files will parse the content syscall.tbl to generate the
header and table files.
ARM, s390 and x86 architecuture does have similar support.
I leverage their implementation to come up with a generic
solution.
Signed-off-by: Firoz Khan <firoz.khan@linaro.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Firoz Khan [Mon, 17 Dec 2018 10:40:35 +0000 (16:10 +0530)]
powerpc: split compat syscall table out from native table
PowerPC uses a syscall table with native and compat calls
interleaved, which is a slightly simpler way to define two
matching tables.
As we move to having the tables generated, that advantage
is no longer important, but the interleaved table gets in
the way of using the same scripts as on the other archit-
ectures.
Split out a new compat_sys_call_table symbol that contains
all the compat calls, and leave the main table for the nat-
ive calls, to more closely match the method we use every-
where else.
Firoz Khan [Mon, 17 Dec 2018 10:40:33 +0000 (16:10 +0530)]
powerpc: move macro definition from asm/systbl.h
Move the macro definition for compat_sys_sigsuspend from
asm/systbl.h to the file which it is getting included.
One of the patch in this patch series is generating uapi
header and syscall table files. In order to come up with
a common implimentation across all architecture, we need
to do this change.
This change will simplify the implementation of system
call table generation script and help to come up a common
implementation across all architecture.
Signed-off-by: Firoz Khan <firoz.khan@linaro.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Firoz Khan [Mon, 17 Dec 2018 10:40:32 +0000 (16:10 +0530)]
powerpc: add __NR_syscalls along with NR_syscalls
NR_syscalls macro holds the number of system call exist
in powerpc architecture. We have to change the value of
NR_syscalls, if we add or delete a system call.
One of the patch in this patch series has a script which
will generate a uapi header based on syscall.tbl file.
The syscall.tbl file contains the number of system call
information. So we have two option to update NR_syscalls
value.
1. Update NR_syscalls in asm/unistd.h manually by count-
ing the no.of system calls. No need to update NR_sys-
calls until we either add a new system call or delete
existing system call.
2. We can keep this feature in above mentioned script,
that will count the number of syscalls and keep it in
a generated file. In this case we don't need to expli-
citly update NR_syscalls in asm/unistd.h file.
The 2nd option will be the recommended one. For that, I
added the __NR_syscalls macro in uapi/asm/unistd.h along
with NR_syscalls asm/unistd.h. The macro __NR_syscalls
also added for making the name convention same across all
architecture. While __NR_syscalls isn't strictly part of
the uapi, having it as part of the generated header to
simplifies the implementation. We also need to enclose
this macro with #ifdef __KERNEL__ to avoid side effects.
Signed-off-by: Firoz Khan <firoz.khan@linaro.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ram Pai [Thu, 20 Dec 2018 20:03:30 +0000 (12:03 -0800)]
powerpc/pkeys: Fix handling of pkey state across fork()
Protection key tracking information is not copied over to the
mm_struct of the child during fork(). This can cause the child to
erroneously allocate keys that were already allocated. Any allocated
execute-only key is lost aswell.
Add code; called by dup_mmap(), to copy the pkey state from parent to
child explicitly.
This problem was originally found by Dave Hansen on x86, which turns
out to be a problem on powerpc aswell.
Greg Kurz [Tue, 11 Dec 2018 17:58:21 +0000 (18:58 +0100)]
ocxl: Fix endiannes bug in read_afu_name()
The AFU Descriptor Template in the PCI config space has a Name Space
field which is a 24 Byte ASCII character string of descriptive name
space for the AFU. The OCXL driver read the string four characters at
a time with pci_read_config_dword().
This optimization is valid on a little-endian system since this is PCI,
but a big-endian system ends up with each subset of four characters in
reverse order.
This could be fixed by switching to read characters one by one. Another
option is to swap the bytes if we're big-endian.
Go for the latter with le32_to_cpu().
Cc: stable@vger.kernel.org # v4.16 Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Breno Leitao [Mon, 26 Nov 2018 20:12:00 +0000 (18:12 -0200)]
powerpc/tm: Unset MSR[TS] if not recheckpointing
There is a TM Bad Thing bug that can be caused when you return from a
signal context in a suspended transaction but with ucontext MSR[TS] unset.
This forces regs->msr[TS] to be set at syscall entrance (since the CPU
state is transactional). It also calls treclaim() to flush the transaction
state, which is done based on the live (mfmsr) MSR state.
Since user context MSR[TS] is not set, then restore_tm_sigcontexts() is not
called, thus, not executing recheckpoint, keeping the CPU state as not
transactional. When calling rfid, SRR1 will have MSR[TS] set, but the CPU
state is non transactional, causing the TM Bad Thing with the following
stack:
[ 33.862316] Bad kernel stack pointer 3fffd9dce3e0 at c00000000000c47c
cpu 0x8: Vector: 700 (Program Check) at [c00000003ff7fd40]
pc: c00000000000c47c: fast_exception_return+0xac/0xb4
lr: 00003fff865f442c
sp: 3fffd9dce3e0
msr: 8000000102a03031
current = 0xc00000041f68b700
paca = 0xc00000000fb84800 softe: 0 irq_happened: 0x01
pid = 1721, comm = tm-signal-sigre
Linux version 4.9.0-3-powerpc64le (debian-kernel@lists.debian.org) (gcc version 6.3.0 20170516 (Debian 6.3.0-18) ) #1 SMP Debian 4.9.30-2+deb9u2 (2017-06-26)
WARNING: exception is not recoverable, can't continue
The same problem happens on 32-bits signal handler, and the fix is very
similar, if tm_recheckpoint() is not executed, then regs->msr[TS] should be
zeroed.
This patch also fixes a sparse warning related to lack of indentation when
CONFIG_PPC_TRANSACTIONAL_MEM is set.
Fixes: 2b0a576d15e0e ("powerpc: Add new transactional memory state to the signal context") CC: Stable <stable@vger.kernel.org> # 3.10+ Signed-off-by: Breno Leitao <leitao@debian.org> Tested-by: Michal Suchánek <msuchanek@suse.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Breno Leitao [Mon, 26 Nov 2018 20:11:59 +0000 (18:11 -0200)]
powerpc/tm: Print scratch value
Usually a TM Bad Thing exception is raised due to three different problems.
a) touching SPRs in an active transaction; b) using TM instruction with the
facility disabled and c) setting a wrong MSR/SRR1 at RFID.
The two initial cases are easy to identify by looking at the instructions.
The latter case is harder, because the MSR is masked after RFID, so, it is
very useful to look at the previous MSR (SRR1) before RFID as also the
current and masked MSR.
Since MSR is saved at paca just before RFID, this patch prints it if a TM
Bad thing happen, helping to understand what is the invalid TM transition
that is causing the exception.
Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Breno Leitao [Mon, 26 Nov 2018 20:11:58 +0000 (18:11 -0200)]
powerpc/tm: Save MSR to PACA before RFID
As other exit points, move SRR1 (MSR) into paca->tm_scratch, so, if
there is a TM Bad Thing in RFID, it is easy to understand what was the
SRR1 value being used.
Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Breno Leitao [Wed, 21 Nov 2018 19:21:09 +0000 (17:21 -0200)]
powerpc/tm: Set MSR[TS] just prior to recheckpoint
On a signal handler return, the user could set a context with MSR[TS] bits
set, and these bits would be copied to task regs->msr.
At restore_tm_sigcontexts(), after current task regs->msr[TS] bits are set,
several __get_user() are called and then a recheckpoint is executed.
This is a problem since a page fault (in kernel space) could happen when
calling __get_user(). If it happens, the process MSR[TS] bits were
already set, but recheckpoint was not executed, and SPRs are still invalid.
The page fault can cause the current process to be de-scheduled, with
MSR[TS] active and without tm_recheckpoint() being called. More
importantly, without TEXASR[FS] bit set also.
Since TEXASR might not have the FS bit set, and when the process is
scheduled back, it will try to reclaim, which will be aborted because of
the CPU is not in the suspended state, and, then, recheckpoint. This
recheckpoint will restore thread->texasr into TEXASR SPR, which might be
zero, hitting a BUG_ON().
This patch simply delays the MSR[TS] set, so, if there is any page fault in
the __get_user() section, it does not have regs->msr[TS] set, since the TM
structures are still invalid, thus avoiding doing TM operations for
in-kernel exceptions and possible process reschedule.
With this patch, the MSR[TS] will only be set just before recheckpointing
and setting TEXASR[FS] = 1, thus avoiding an interrupt with TM registers in
invalid state.
Other than that, if CONFIG_PREEMPT is set, there might be a preemption just
after setting MSR[TS] and before tm_recheckpoint(), thus, this block must
be atomic from a preemption perspective, thus, calling
preempt_disable/enable() on this code.
It is not possible to move tm_recheckpoint to happen earlier, because it is
required to get the checkpointed registers from userspace, with
__get_user(), thus, the only way to avoid this undesired behavior is
delaying the MSR[TS] set.
The 32-bits signal handler seems to be safe this current issue, but, it
might be exposed to the preemption issue, thus, disabling preemption in
this chunk of code.
Changes from v2:
* Run the critical section with preempt_disable.
Fixes: 87b4e5393af7 ("powerpc/tm: Fix return of active 64bit signals") Cc: stable@vger.kernel.org (v3.9+) Signed-off-by: Breno Leitao <leitao@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/fadump: Do not allow hot-remove memory from fadump reserved area.
For fadump to work successfully there should not be any holes in reserved
memory ranges where kernel has asked firmware to move the content of old
kernel memory in event of crash. Now that fadump uses CMA for reserved
area, this memory area is now not protected from hot-remove operations
unless it is cma allocated. Hence, fadump service can fail to re-register
after the hot-remove operation, if hot-removed memory belongs to fadump
reserved region. To avoid this make sure that memory from fadump reserved
area is not hot-removable if fadump is registered.
However, if user still wants to remove that memory, he can do so by
manually stopping fadump service before hot-remove operation.
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/fadump: Throw proper error message on fadump registration failure
fadump fails to register when there are holes in reserved memory area.
This can happen if user has hot-removed a memory that falls in the
fadump reserved memory area. Throw a meaningful error message to the
user in such case.
One of the primary issues with Firmware Assisted Dump (fadump) on Power
is that it needs a large amount of memory to be reserved. On large
systems with TeraBytes of memory, this reservation can be quite
significant.
In some cases, fadump fails if the memory reserved is insufficient, or
if the reserved memory was DLPAR hot-removed.
In the normal case, post reboot, the preserved memory is filtered to
extract only relevant areas of interest using the makedumpfile tool.
While the tool provides flexibility to determine what needs to be part
of the dump and what memory to filter out, all supported distributions
default this to "Capture only kernel data and nothing else".
We take advantage of this default and the Linux kernel's Contiguous
Memory Allocator (CMA) to fundamentally change the memory reservation
model for fadump.
Instead of setting aside a significant chunk of memory nobody can use,
this patch uses CMA instead, to reserve a significant chunk of memory
that the kernel is prevented from using (due to MIGRATE_CMA), but
applications are free to use it. With this fadump will still be able
to capture all of the kernel memory and most of the user space memory
except the user pages that were present in CMA region.
Essentially, on a P9 LPAR with 2 cores, 8GB RAM and current upstream:
[root@zzxx-yy10 ~]# free -m
total used free shared buff/cache available
Mem: 7557 193 6822 12 541 6725
Swap: 4095 0 4095
With this patch:
[root@zzxx-yy10 ~]# free -m
total used free shared buff/cache available
Mem: 8133 194 7464 12 475 7338
Swap: 4095 0 4095
Changes made here are completely transparent to how fadump has
traditionally worked.
Thanks to Aneesh Kumar and Anshuman Khandual for helping us understand
CMA and its usage.
TODO:
- Handle case where CMA reservation spans nodes.
Signed-off-by: Ananth N Mavinakayanahalli <ananth@linux.vnet.ibm.com> Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/powernv: Move opal_power_control_init() call in opal_init().
opal_power_control_init() depends on opal message notifier to be
initialized, which is done in opal_init()->opal_message_init(). But both
these initialization are called through machine initcalls and it all
depends on in which order they being called. So far these are called in
correct order (may be we got lucky) and never saw any issue. But it is
clearer to control initialization order explicitly by moving
opal_power_control_init() into opal_init().
Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
CONFIG_PCI_MSI was made mandatory by commit a311e738b6d8
("powerpc/powernv: Make PCI non-optional") so the #ifdef
checks around CONFIG_PCI_MSI here can be removed entirely.
Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Reviewed-by: Joel Stanley <joel@jms.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Ravi Bangoria [Wed, 21 Nov 2018 03:56:37 +0000 (09:26 +0530)]
Powerpc/perf: Wire up PMI throttling
Commit 14c63f17b1fde ("perf: Drop sample rate when sampling is too
slow") introduced a way to throttle PMU interrupts if we're spending
too much time just processing those. Wire up powerpc PMI handler to
use this infrastructure.
We have throttling of the *rate* of interrupts, but this adds
throttling based on the *time taken* to process the interrupts.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/powernv/eeh/npu: Fix uninitialized variables in opal_pci_eeh_freeze_status
The current implementation of the OPAL_PCI_EEH_FREEZE_STATUS call in
skiboot's NPU driver does not touch the pci_error_type parameter so
it might have garbage but the powernv code analyzes it nevertheless.
This initializes pcierr and fstate to zero in all call sites.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: Sam Bobroff <sbobroff@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/powernv/ioda: Reduce a number of hooks in pnv_phb
fixup_phb() is never used, this removes it.
pick_m64_pe() and reserve_m64_pe() are always defined for all powernv
PHBs: they are initialized by pnv_ioda_parse_m64_window() which is
called unconditionally from pnv_pci_init_ioda_phb() which initializes
all known PHB types on powernv so we can open code them.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
As a part of cleanup, the SPAPR TCE IOMMU subdriver releases preregistered
memory. If there is a bug in memory release, the loop in
tce_iommu_release() becomes infinite; this actually happened to me.
This makes the loop finite and prints a warning on every failure to make
the code more bug prone.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/powernv/ioda: Allocate indirect TCE levels of cached userspace addresses on demand
The powernv platform maintains 2 TCE tables for VFIO - a hardware TCE
table and a table with userspace addresses; the latter is used for
marking pages dirty when corresponging TCEs are unmapped from
the hardware table.
a68bd1267b72 ("powerpc/powernv/ioda: Allocate indirect TCE levels
on demand") enabled on-demand allocation of the hardware table,
however it missed the other table so it has still been fully allocated
at the boot time. This fixes the issue by allocating a single level,
just like we do for the hardware table.
Fixes: a68bd1267b72 ("powerpc/powernv/ioda: Allocate indirect TCE levels on demand") Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diana Craciun [Wed, 12 Dec 2018 14:03:06 +0000 (16:03 +0200)]
powerpc/fsl: Flush the branch predictor at each kernel entry (32 bit)
In order to protect against speculation attacks on
indirect branches, the branch predictor is flushed at
kernel entry to protect for the following situations:
- userspace process attacking another userspace process
- userspace process attacking the kernel
Basically when the privillege level change (i.e.the kernel
is entered), the branch predictor state is flushed.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diana Craciun [Wed, 12 Dec 2018 14:03:05 +0000 (16:03 +0200)]
powerpc/fsl: Flush the branch predictor at each kernel entry (64bit)
In order to protect against speculation attacks on
indirect branches, the branch predictor is flushed at
kernel entry to protect for the following situations:
- userspace process attacking another userspace process
- userspace process attacking the kernel
Basically when the privillege level change (i.e. the
kernel is entered), the branch predictor state is flushed.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diana Craciun [Wed, 12 Dec 2018 14:03:03 +0000 (16:03 +0200)]
powerpc/fsl: Emulate SPRN_BUCSR register
In order to flush the branch predictor the guest kernel performs
writes to the BUCSR register which is hypervisor privilleged. However,
the branch predictor is flushed at each KVM entry, so the branch
predictor has been already flushed, so just return as soon as possible
to guest.
Diana Craciun [Wed, 12 Dec 2018 14:03:00 +0000 (16:03 +0200)]
powerpc/fsl: Add infrastructure to fixup branch predictor flush
In order to protect against speculation attacks (Spectre
variant 2) on NXP PowerPC platforms, the branch predictor
should be flushed when the privillege level is changed.
This patch is adding the infrastructure to fixup at runtime
the code sections that are performing the branch predictor flush
depending on a boot arg parameter which is added later in a
separate patch.
Signed-off-by: Diana Craciun <diana.craciun@nxp.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Mon, 17 Dec 2018 14:18:27 +0000 (14:18 +0000)]
powerpc/prom: move the device tree if not in declared memory.
If the device tree doesn't reside in the memory which is declared
inside it, it has to be moved as well as this memory will not be
mapped by the kernel.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Add some documentation on which CPU versions map to which ISA
versions. This is all publicly available information, some of it
already in the kernel source, but it's much nicer to have it all in
one place.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Fri, 14 Dec 2018 13:57:11 +0000 (00:57 +1100)]
powerpc/configs: Don't enable PPC_EARLY_DEBUG in defconfigs
This reverts the remains of commit b9ef7d6b11c1 ("powerpc: Update
default configurations").
That commit was proceeded by a commit which added a config option to
control use of BOOTX for early debug, ie. PPC_EARLY_DEBUG_BOOTX, and
then the update of the defconfigs was intended to not change behaviour
by then enabling the new config option.
However enabling PPC_EARLY_DEBUG had other consequences, notably
causing us to register the udbg console at the end of udbg_early_init().
This means on a system which doesn't have anything that BOOTX can
use (most systems), we register the udbg console very early but the
bootx code just throws everything away, meaning early boot messages
are never printed to the console.
What we want to happen is for the udbg console to only be registered
later (from setup_arch()) once we've setup udbg_putc, and then all
early boot messages will be replayed.
Arnd Bergmann [Mon, 10 Dec 2018 21:51:57 +0000 (22:51 +0100)]
powerpc: eeh_event: convert semaphore to completion
For this use case, completions and semaphores are equivalent,
but semaphores are an awkward interface that should generally
be avoided, so use the completion instead.
Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Greg Kurz [Mon, 10 Dec 2018 15:13:38 +0000 (16:13 +0100)]
ocxl/afu_irq: Don't include <asm/pnv-ocxl.h>
The AFU irq code doesn't need to reach out to the platform.
Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Greg Kurz [Mon, 10 Dec 2018 15:18:13 +0000 (16:18 +0100)]
ocxl: Clarify error path in setup_xsl_irq()
Implementing rollback with goto and labels is a common practice that
leads to prettier and more maintainable code. FWIW, this design pattern
is already being used in alloc_link() a few lines below in this file.
Do the same in setup_xsl_irq().
Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Frederic Barrat <fbarrat@linux.ibm.com> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
The bamboo dts has a bug: it uses a non-naturally aligned range
for PCI memory space. This isnt' supported by the code, thus
causing PCI to break on this system.
This is due to the fact that while the chip memory map has 1G
reserved for PCI memory, it's only 512M aligned. The code doesn't
know how to split that into 2 different PMMs and fails, so limit
the region to 512M.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Darren Stevens [Sun, 19 Aug 2018 20:21:55 +0000 (21:21 +0100)]
powerpc/pasemi: Add PCI initialisation for Nemo board.
The A-Eon Amigaone X1000's Nemo motherboard has an AMD SB600
connected to one of the PCI-e root ports on its PaSemi
Pwrficient 1628M SoC. Normally the SB600 southbridge would be
connected to a hidden PCI-e port on the system's northbridge,
and as a result doesn't fully comply with the PCI-e spec.
Add code to relax the PCI-e detection in both the root port
and the Linux kernel allowing on board devices to be detected.
Signed-off-by: Darren Stevens <darren@stevens-zone.net> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Fri, 14 Dec 2018 15:23:33 +0000 (15:23 +0000)]
powerpc/mm: Make NULL pointer deferences explicit on bad page faults.
As several other arches including x86, this patch makes it explicit
that a bad page fault is a NULL pointer dereference when the fault
address is lower than PAGE_SIZE
In the mean time, this page makes all bad_page_fault() messages
shorter so that they remain on one single line. And it prefixes them
by "BUG: " so that they get easily grepped.
The CXL code never even looks at the dma mask, so there is no good
reason for this sanity check. Remove it because it gets in the way
of the dma ops refactoring.
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/dma: split the two __dma_alloc_coherent implementations
The implemementation for the CONFIG_NOT_COHERENT_CACHE case doesn't share
any code with the one for systems with coherent caches. Split it off
and merge it with the helpers in dma-noncoherent.c that have no other
callers.
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/dma: remove the unused ISA_DMA_THRESHOLD export
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/dma: remove the unused ARCH_HAS_DMA_MMAP_COHERENT define
Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This function is internal to the DMA API implementation. Instead use
the DMA API to properly unmap. Note that the DMA API usage in this
driver is a disaster and urgently needs some work - it is missing all
the unmaps, seems to do a secondary map where it looks like it should
to a unmap in one place to work around cache coherency and the
directions passed in seem to be partially wrong.
Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Christian Lamparter <chunkeey@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/dma: properly wire up the unmap_page and unmap_sg methods
The unmap methods need to transfer memory ownership back from the
device to the cpu by identical means as dma_sync_*_to_cpu. I'm not
sure powerpc needs to do any work in this transfer direction, but
given that it does invalidate the caches in dma_sync_*_to_cpu already
we should make sure we also do so on unmapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[mpe: s/dir/direction in dma_nommu_unmap_page()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Fri, 14 Dec 2018 10:27:47 +0000 (10:27 +0000)]
powerpc/prom: fix early DEBUG messages
This patch fixes early DEBUG messages in prom.c:
- Use %px instead of %p to see the addresses
- Cast memblock_phys_mem_size() with (unsigned long long) to
avoid build failure when phys_addr_t is not 64 bits.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Greg Kurz [Sun, 16 Dec 2018 21:28:50 +0000 (22:28 +0100)]
ocxl: Fix endiannes bug in ocxl_link_update_pe()
All fields in the PE are big-endian. Use cpu_to_be32() like everywhere
else something is written to the PE. Otherwise a wrong TID will be used
by the NPU. If this TID happens to point to an existing thread sharing
the same mm, it could be woken up by error. This is highly improbable
though. The likely outcome of this is the NPU not finding the target
thread and forcing the AFU into sending an interrupt, which userspace
is supposed to handle anyway.
Fixes: e948e06fc63a ("ocxl: Expose the thread_id needed for wait on POWER9") Cc: stable@vger.kernel.org # v4.18 Signed-off-by: Greg Kurz <groug@kaod.org> Acked-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Joel Stanley [Mon, 12 Nov 2018 05:28:06 +0000 (15:58 +1030)]
powerpc/32: Avoid unsupported flags with clang
When building for ppc32 with clang these flags are unsupported:
-ffixed-r2 and -mmultiple
llvm's lib/Target/PowerPC/PPCRegisterInfo.cpp marks r2 as reserved on
when building for SVR4ABI and !ppc64:
// The SVR4 ABI reserves r2 and r13
if (Subtarget.isSVR4ABI()) {
// We only reserve r2 if we need to use the TOC pointer. If we have no
// explicit uses of the TOC pointer (meaning we're a leaf function with
// no constant-pool loads, etc.) and we have no potential uses inside an
// inline asm block, then we can treat r2 has an ordinary callee-saved
// register.
const PPCFunctionInfo *FuncInfo = MF.getInfo<PPCFunctionInfo>();
if (!TM.isPPC64() || FuncInfo->usesTOCBasePtr() || MF.hasInlineAsm())
markSuperRegs(Reserved, PPC::R2); // System-reserved register
markSuperRegs(Reserved, PPC::R13); // Small Data Area pointer register
}
This means we can safely omit -ffixed-r2 when building for 32-bit
targets.
The -mmultiple/-mno-multiple flags are not supported by clang, so
platforms that might support multiple miss out on using multiple word
instructions.
We wrap these flags in cc-option so that when Clang gains support the
kernel will be able use these flags.
Clang 8 can then build a ppc44x_defconfig which boots in Qemu:
make CC=clang-8 ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu- ppc44x_defconfig
./scripts/config -e CONFIG_DEVTMPFS -d DEVTMPFS_MOUNT
make CC=clang-8 ARCH=powerpc CROSS_COMPILE=powerpc-linux-gnu-
Joel Stanley [Fri, 2 Nov 2018 00:44:55 +0000 (11:14 +1030)]
raid6/ppc: Fix build for clang
We cannot build these files with clang as it does not allow altivec
instructions in assembly when -msoft-float is passed.
Jinsong Ji <jji@us.ibm.com> wrote:
> We currently disable Altivec/VSX support when enabling soft-float. So
> any usage of vector builtins will break.
>
> Enable Altivec/VSX with soft-float may need quite some clean up work, so
> I guess this is currently a limitation.
>
> Removing -msoft-float will make it work (and we are lucky that no
> floating point instructions will be generated as well).
This is a workaround until the issue is resolved in clang.
powerpc/perf: Add constraints for power9 l2/l3 bus events
In previous generation processors, both bus events and direct
events of performance monitoring unit can be individually
programmabled and monitored in PMCs.
But in Power9, L2/L3 bus events are always available as a
"bank" of 4 events. To obtain the counts for any of the
l2/l3 bus events in a given bank, the user will have to
program PMC4 with corresponding l2/l3 bus event for that
bank.
Patch enforce two contraints incase of L2/L3 bus events.
1)Any L2/L3 event when programmed is also expected to program corresponding
PMC4 event from that group.
2)PMC4 event should always been programmed first due to group constraint
logic limitation
Raw event code has couple of fields "unit" and "cache" in it, to capture
the "unit" to monitor for a given pmcxsel and cache reload qualifier to
program in MMCR1.
isa207_get_constraint() refers "unit" field to update the MMCRC (L2/L3)
Event bus control fields with "cache" bits of the raw event code.
These are power8 specific and not supported by PowerISA v3.0 pmu. So wrap
the checks to be power8 specific. Also, "cache" bit field is referred to
update MMCR1[16:17] and this check can be power8 specific.
Fixes: 7ffd948fae4cd ('powerpc/perf: factor out power8 pmu functions') Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/perf: Update perf_regs structure to include SIER
On each sample, Sample Instruction Event Register (SIER) content
is saved in pt_regs. SIER does not have a entry as-is in the pt_regs
but instead, SIER content is saved in the "dar" register of pt_regs.
Patch adds another entry to the perf_regs structure to include the "SIER"
printing which internally maps to the "dar" of pt_regs.
It also check for the SIER availability in the platform and present
value accordingly
Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/perf: Fix thresholding counter data for unknown type
MMCRA[34:36] and MMCRA[38:44] expose the thresholding counter value.
Thresholding counter can be used to count latency cycles such as
load miss to reload. But threshold counter value is not relevant
when the sampled instruction type is unknown or reserved. Patch to
fix the thresholding counter value to zero when sampled instruction
type is unknown or reserved.
Fixes: 170a315f41c6('powerpc/perf: Support to export MMCRA[TEC*] field to userspace') Signed-off-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm/hash: Handle user access of kernel address gracefully
In commit 2865d08dd9ea ("powerpc/mm: Move the DSISR_PROTFAULT sanity
check") we moved the protection fault access check before the vma
lookup. That means we hit that WARN_ON when user space accesses a
kernel address. Before that commit this was handled by find_vma() not
finding vma for the kernel address and considering that access as bad
area access.
Avoid the confusing WARN_ON and convert that to a ratelimited printk.
for exec:
a.out[6067]: User access of kernel address (c00000000000dea0) - exploit attempt? (uid: 1000)
a.out[6067]: segfault (11) at c00000000000dea0 nip c00000000000dea0 lr 129d507b0 code 1
a.out[6067]: Bad NIP, not dumping instructions.
Fixes: 2865d08dd9ea ("powerpc/mm: Move the DSISR_PROTFAULT sanity check") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Tested-by: Breno Leitao <leitao@debian.org>
[mpe: Don't split printk() string across lines] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Wed, 28 Nov 2018 17:21:10 +0000 (17:21 +0000)]
powerpc/mm: add exec protection on powerpc 603
The 603 doesn't have a HASH table, TLB misses are handled by
software. It is then possible to generate page fault when
_PAGE_EXEC is not set like in nohash/32.
There is one "reserved" PTE bit available, this patch uses
it for _PAGE_EXEC.
In order to support it, set_pte_filter() and
set_access_flags_filter() are made common, and the handling
is made dependent on MMU_FTR_HPTE_TABLE
commit f21f49ea639a ("[POWERPC] Remove the dregs of APUS support from
arch/powerpc") removed CONFIG_APUS, but forgot to remove the logic
which adapts tophys() and tovirt() for it.
This patch removes the last stale pieces.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Thu, 18 Oct 2018 05:22:06 +0000 (05:22 +0000)]
powerpc/mm: remove unused variable
In file included from ./include/linux/hugetlb.h:445:0,
from arch/powerpc/kernel/setup-common.c:37:
./arch/powerpc/include/asm/hugetlb.h: In function ‘huge_ptep_clear_flush’:
./arch/powerpc/include/asm/hugetlb.h:154:8: error: variable ‘pte’ set but not used [-Werror=unused-but-set-variable]
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Christophe Leroy [Mon, 10 Dec 2018 08:08:28 +0000 (08:08 +0000)]
lib: fix build failure in CONFIG_DEBUG_VIRTUAL test
On several arches, virt_to_phys() is in io.h
Build fails without it:
CC lib/test_debug_virtual.o
lib/test_debug_virtual.c: In function 'test_debug_virtual_init':
lib/test_debug_virtual.c:26:7: error: implicit declaration of function 'virt_to_phys' [-Werror=implicit-function-declaration]
pa = virt_to_phys(va);
^
Fixes: e4dace361552 ("lib: add test module for CONFIG_DEBUG_VIRTUAL") CC: stable@vger.kernel.org Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Kees Cook <keescook@chromium.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
was added in 2006 in commit f48b8296b315 ("[PATCH] powerpc32: Set cpu
explicitly in kernel compiles"). This change was acceptable since the
TARGET_CPU logic was 64-bit only.
Since commit 0e00a8c9fd92 ("powerpc: Allow CPU selection
also on PPC32") this logic is no longer acceptable after the TARGET_CPU
specific. It currently appends -mcpu=powerpc at the end of the command
line, after any TARGET_CPU specific:
Fixes: 0e00a8c9fd92 ("powerpc: Allow CPU selection also on PPC32") Signed-off-by: Mathieu Malaterre <malat@debian.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
ipic_set_priority() has been unused since 2006 when the last usage was
removed in commit b9f0f1bb2bca ("[POWERPC] Adapt ipic driver to new
host_ops interface, add set_irq_type to set IRQ sense").
Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Michael Ellerman [Mon, 17 Dec 2018 11:11:54 +0000 (22:11 +1100)]
Merge branch 'fixes' into next
Merge our fixes branch again, this has a couple of build fixes and also
a change to do_syscall_trace_enter() that will conflict with a patch we
want to apply in next.
powerpc/ptrace: replace ptrace_report_syscall() with a tracehook call
Arch code should use tracehook_*() helpers, as documented in
include/linux/tracehook.h, ptrace_report_syscall() is not expected to
be used outside that file.
The patch does not look very nice, but at least it is correct
and opens the way for PTRACE_GET_SYSCALL_INFO API.
Co-authored-by: Dmitry V. Levin <ldv@altlinux.org> Fixes: 5521eb4bca2d ("powerpc/ptrace: Add support for PTRACE_SYSEMU") Signed-off-by: Elvira Khabirova <lineprinter@altlinux.org> Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
[mpe: Take this as a minimal fix for 4.20, we'll rework it later] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/mm: Fallback to RAM if the altmap is unusable
The "altmap" is used to provide a pool of memory that is reserved for
the vmemmap backing of hot-plugged memory. This is useful when adding
large amount of ZONE_DEVICE memory to a system with a limited amount of
normal memory.
On ppc64 we use huge pages to map the vmemmap which requires the backing
storage to be contigious and aligned to the hugepage size. The altmap
implementation allows for the altmap provider to reserve a few PFNs at
the start of the range for it's own uses and when this occurs the
first chunk of the altmap is not usable for hugepage mappings. On hash
there is no sane way to fall back to a normal sized page mapping so we
fail the allocation. This results in memory hotplug failing with
ENOMEM when the new range doesn't fall into an existing vmemmap block.
This patch handles this case by falling back to using system memory
rather than failing if we cannot allocate from the altmap. This
fallback should only ever be used for the first vmemmap block so it
should not cause excess memory consumption.
Fixes: 7b73d978a5d0 ("mm: pass the vmem_altmap to vmemmap_populate") Signed-off-by: Oliver O'Halloran <oohall@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
powerpc/papr_scm: Use ibm,unit-guid as the iset cookie
The interleave set cookie is used to determine if a label stored in the
metadata space should be applied to the current region. This is
important in the case of NVDIMMs since the firmware may change the
interleaving configuration of a DIMM which would invalidate the existing
labels. In our case the hypervisor hides those details from us so we
don't really care, but libnvdimm still requires the interleave set
cookie to be non-zero.
For our purposes we just need the set cookie to be unique and fixed for
a given PAPR SCM region and using the unit-guid (really a UUID) is fine
for this purpose.
Fixes: b5beae5e224f ("powerpc/pseries: Add driver for PAPR SCM regions") Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Use kernel types (u64)] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
projects / kernel.git / log