Nikolay Borisov [Mon, 31 May 2021 07:37:03 +0000 (10:37 +0300)]
btrfs: use list_last_entry in add_falloc_range
Instead of calling list_entry with head->prev simply call
list_last_entry which makes it obvious which member of the list is
being referred. This allows to remove the extra 'prev' pointer.
Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Sat, 29 May 2021 09:48:36 +0000 (17:48 +0800)]
btrfs: fix comment about max_out in btrfs_compress_pages
Commit e5d74902362f ("btrfs: derive maximum output size in the
compression implementation") removed @max_out argument in
btrfs_compress_pages() but its comment remained, remove it.
Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Sat, 29 May 2021 09:48:35 +0000 (17:48 +0800)]
btrfs: optimize variables size in btrfs_submit_compressed_write
Patch "btrfs: reduce compressed_bio member's types" reduced some
member's size. Function arguments @len, @compressed_len and @nr_pages
can be declared as unsigned int.
Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Anand Jain [Sat, 29 May 2021 09:48:34 +0000 (17:48 +0800)]
btrfs: optimize variables size in btrfs_submit_compressed_read
Patch "btrfs: reduce compressed_bio member's types" reduced some
member's size. Declare the variables @compressed_len, @nr_pages and
@pg_index size as an unsigned int in the function
btrfs_submit_compressed_read.
Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Fri, 28 May 2021 10:37:32 +0000 (11:37 +0100)]
btrfs: avoid unnecessary logging of xattrs during fast fsyncs
When logging an inode we always log all its xattrs, so that we are able
to figure out which ones should be deleted during log replay. However this
is unnecessary when we are doing a fast fsync and no xattrs were added,
changed or deleted since the last time we logged the inode in the current
transaction.
So skip the logging of xattrs when the inode was previously logged in the
current transaction and no xattrs were added, changed or deleted. If any
changes to xattrs happened, than the inode has BTRFS_INODE_COPY_EVERYTHING
set in its runtime flags and the xattrs get logged. This saves time on
scanning for xattrs, allocating memory, COWing log tree extent buffers and
adding more lock contention on the extent buffers when there are multiple
tasks logging in parallel.
The use of xattrs is common when using ACLs, some applications, or when
using security modules like SELinux where every inode gets a security
xattr added to it.
The following test script, using fio, was used on a box with 12 cores, 64G
of RAM, a NVMe device and the default non-debug kernel config from Debian.
It uses 8 concurrent jobs each writing in blocks of 64K to its own 4G file,
each file with a single xattr of 50 bytes (about the same size for an ACL
or SELinux xattr), doing random buffered writes with an fsync after each
write.
$ cat test.sh
#!/bin/bash
DEV=/dev/nvme0n1
MNT=/mnt/test
MOUNT_OPTIONS="-o ssd"
MKFS_OPTIONS="-d single -m single"
David Sterba [Fri, 14 May 2021 19:21:27 +0000 (21:21 +0200)]
btrfs: add device delete cancel
Accept device name "cancel" as a request to cancel running device
deletion operation. The string is literal, in case there's a real device
named "cancel", pass it as full absolute path or as "./cancel"
This works for v1 and v2 ioctls when the device is specified by name.
Moving chunks from the device uses relocation, use the conditional
exclusive operation start and cancellation helpers
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Tue, 18 May 2021 19:12:33 +0000 (21:12 +0200)]
btrfs: add cancellation to resize
Accept literal string "cancel" as resize operation and interpret that
as a request to cancel the running operation. If it's running, wait
until it finishes current work and return ECANCELED.
Shrinking resize uses relocation to move the chunks away, use the
conditional exclusive operation start and cancellation helpers.
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Fri, 14 May 2021 19:32:44 +0000 (21:32 +0200)]
btrfs: add wrapper for conditional start of exclusive operation
To support optional cancellation of some operations, add helper that will
wrap all the combinations. In normal mode it's same as
btrfs_exclop_start, in cancellation mode it checks if it's already
running and request cancellation and waits until completion.
The error codes can be returned to to user space and semantics is not
changed, adding ECANCELED. This should be evaluated as an error and that
the operation has not completed and the operation should be restarted
or the filesystem status reviewed.
David Sterba [Tue, 18 May 2021 19:05:52 +0000 (21:05 +0200)]
btrfs: introduce try-lock semantics for exclusive op start
Add try-lock for exclusive operation start to allow callers to do more
checks. The same operation must already be running. The try-lock and
unlock must pair and are a substitute for btrfs_exclop_start, thus it
must also pair with btrfs_exclop_finish to release the exclop context.
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 17 May 2021 22:37:36 +0000 (00:37 +0200)]
btrfs: add cancellable chunk relocation support
Add support code that will allow canceling relocation on the chunk
granularity. This is different and independent of balance, that also
uses relocation but is a higher level operation and manages it's own
state and pause/cancellation requests.
Relocation is used for resize (shrink) and device deletion so this will
be a common point to implement cancellation for both. The context is
entirely in btrfs_relocate_block_group and btrfs_recover_relocation,
enclosing one chunk relocation. The status bit is set and unset between
the chunks. As relocation can take long, the effects may not be
immediate and the request and actual action can slightly race.
The fs_info::reloc_cancel_req is only supposed to be increased and does
not pair with decrement like fs_info::balance_cancel_req.
Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Fri, 14 May 2021 15:42:30 +0000 (17:42 +0200)]
btrfs: protect exclusive_operation by super_lock
The exclusive operation is now atomically checked and set using bit
operations. Switch it to protection by spinlock. The super block lock is
not frequently used and adding a new lock seems like an overkill so it
should be safe to reuse it.
The reason to use spinlock is to enhance the locking context so more
checks can be done, eg. allowing the same exclusive operation enter
the exclop section and cancel the running one. This will be used for
resize and device delete.
Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 21 Sep 2020 20:07:14 +0000 (22:07 +0200)]
btrfs: clean up header members offsets in write helpers
Move header offsetof() to the expression that calculates the address so
it's part of get_eb_offset_in_page where the 2nd parameter is the member
offset.
Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 21 Sep 2020 20:07:14 +0000 (22:07 +0200)]
btrfs: simplify eb checksum verification in btrfs_validate_metadata_buffer
The verification copies the calculated checksum bytes to a temporary
buffer but this is not necessary. We can map the eb header on the first
page and use the checksum bytes directly.
This saves at least one function call and boundary checks so it could
lead to a minor performance improvement.
Reviewed-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Mon, 14 Oct 2019 12:38:33 +0000 (14:38 +0200)]
btrfs: reduce compressed_bio members' types
Several members of compressed_bio are of type that's unnecessarily big
for the values that they'd hold:
- the size of the uncompressed and compressed data is 128K now, we can
keep is as int
- same for number of pages
- the compress type fits to a byte
- the errors is 0/1
The size of the unpatched structure is 80 bytes with several holes.
Reordering nr_pages next to the pages the hole after pending_bios is
filled and the resulting size is 56 bytes. This keeps the csums array
aligned to 8 bytes, which is nice. Further size optimizations may be
possible but right now it looks good to me:
David Sterba [Tue, 7 Jul 2020 16:38:05 +0000 (18:38 +0200)]
btrfs: clear log tree recovering status if starting transaction fails
When a log recovery is in progress, lots of operations have to take that
into account, so we keep this status per tree during the operation. Long
time ago error handling revamp patch 79787eaab461 ("btrfs: replace many
BUG_ONs with proper error handling") removed clearing of the status in
an error branch. Add it back as was intended in e02119d5a7b4 ("Btrfs:
Add a write ahead tree log to optimize synchronous operations").
There are probably no visible effects, log replay is done only during
mount and if it fails all structures are cleared so the stale status
won't be kept.
Fixes: 79787eaab461 ("btrfs: replace many BUG_ONs with proper error handling") Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Tue, 7 Jul 2020 16:30:06 +0000 (18:30 +0200)]
btrfs: clear defrag status of a root if starting transaction fails
The defrag loop processes leaves in batches and starting transaction for
each. The whole defragmentation on a given root is protected by a bit
but in case the transaction fails, the bit is not cleared
In case the transaction fails the bit would prevent starting
defragmentation again, so make sure it's cleared.
David Sterba [Fri, 7 May 2021 18:00:14 +0000 (20:00 +0200)]
btrfs: sysfs: fix format string for some discard stats
The type of discard_bitmap_bytes and discard_extent_bytes is u64 so the
format should be %llu, though the actual values would hardly ever
overflow to negative values.
Josef Bacik [Thu, 20 May 2021 15:21:31 +0000 (11:21 -0400)]
btrfs: always abort the transaction if we abort a trans handle
While stress testing our error handling I noticed that sometimes we
would still commit the transaction even though we had aborted the
transaction.
Currently we track if a trans handle has dirtied any metadata, and if it
hasn't we mark the filesystem as having an error (so no new transactions
can be started), but we will allow the current transaction to complete
as we do not mark the transaction itself as having been aborted.
This sounds good in theory, but we were not properly tracking IO errors
in btrfs_finish_ordered_io, and thus committing the transaction with
bogus free space data. This isn't necessarily a problem per-se with the
free space cache, as the other guards in place would have kept us from
accepting the free space cache as valid, but highlights a real world
case where we had a bug and could have corrupted the filesystem because
of it.
This "skip abort on empty trans handle" is nice in theory, but assumes
we have perfect error handling everywhere, which we clearly do not.
Also we do not allow further transactions to be started, so all this
does is save the last transaction that was happening, which doesn't
necessarily gain us anything other than the potential for real
corruption.
Remove this particular bit of code, if we decide we need to abort the
transaction then abort the current one and keep us from doing real harm
to the file system, regardless of whether this specific trans handle
dirtied anything or not.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Filipe Manana [Mon, 24 May 2021 10:35:55 +0000 (11:35 +0100)]
btrfs: don't set the full sync flag when truncation does not touch extents
At btrfs_truncate() where we truncate the inode either to the same size
or to a smaller size, we always set the full sync flag on the inode.
This is needed in case the truncation drops or trims any file extent items
that start beyond or cross the new inode size, so that the next fsync
drops all inode items from the log and scans again the fs/subvolume tree
to find all items that must be logged.
However if the truncation does not drop or trims any file extent items, we
do not need to set the full sync flag and force the next fsync to use the
slow code path. So do not set the full sync flag in such cases.
One use case where it is frequent to do truncations that do not change
the inode size and do not drop any extents (no prealloc extents beyond
i_size) is when running Microsoft's SQL Server inside a Docker container.
One example workload is the one Philipp Fent reported recently, in the
thread with a link below. In this workload a large number of fsyncs are
preceded by such truncate operations.
After this change I constantly get the runtime for that workload from
Philipp to be reduced by about -12%, for example from 184 seconds down
to 162 seconds.
Filipe Manana [Mon, 24 May 2021 10:35:54 +0000 (11:35 +0100)]
btrfs: fix misleading and incomplete comment of btrfs_truncate()
The comment at the top of btrfs_truncate() mentions that csum items are
dropped or truncated to the new i_size, but this is wrong and non sense,
as they are unrelated to the i_size and are located in the csums tree and
not on a tree with inode items (fs/subvolume tree or a log tree). Instead
that claim applies to file extent items, so fix the comment to refer to
them instead.
While at it make the whole comment for the function more descriptive and
follow the kernel doc style.
Tested-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Fri, 21 May 2021 20:44:09 +0000 (16:44 -0400)]
btrfs: abort transaction if we fail to update the delayed inode
If we fail to update the delayed inode we need to abort the transaction,
because we could leave an inode with the improper counts or some other
such corruption behind.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Fri, 21 May 2021 20:44:08 +0000 (16:44 -0400)]
btrfs: fix error handling in __btrfs_update_delayed_inode
If we get an error while looking up the inode item we'll simply bail
without cleaning up the delayed node. This results in this style of
warning happening on commit:
Because the iref isn't dropped and this leaves an elevated node->count,
so any release just re-queues it onto the delayed inodes list. Fix this
by going to the out label to handle the proper cleanup of the delayed
node.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Fri, 21 May 2021 20:44:07 +0000 (16:44 -0400)]
btrfs: make btrfs_release_delayed_iref handle the !iref case
Right now we only cleanup the delayed iref if we have
BTRFS_DELAYED_NODE_DEL_IREF set on the node. However we have some error
conditions that need to cleanup the iref if it still exists, so to make
this code cleaner move the test_bit into btrfs_release_delayed_iref
itself and unconditionally call it in each of the cases instead.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
David Sterba [Wed, 9 Oct 2019 11:58:13 +0000 (13:58 +0200)]
btrfs: scrub: per-device bandwidth control
Add sysfs interface to limit io during scrub. We relied on the ionice
interface to do that, eg. the idle class let the system usable while
scrub was running. This has changed when mq-deadline got widespread and
did not implement the scheduling classes. That was a CFQ thing that got
deleted. We've got numerous complaints from users about degraded
performance.
Currently only BFQ supports that but it's not a common scheduler and we
can't ask everybody to switch to it.
Alternatively the cgroup io limiting can be used but that also a
non-trivial setup (v2 required, the controller must be enabled on the
system). This can still be used if desired.
Other ideas that have been explored: piggy-back on ionice (that is set
per-process and is accessible) and interpret the class and classdata as
bandwidth limits, but this does not have enough flexibility as there are
only 8 allowed and we'd have to map fixed limits to each value. Also
adjusting the value would need to lookup the process that currently runs
scrub on the given device, and the value is not sticky so would have to
be adjusted each time scrub runs.
Running out of options, sysfs does not look that bad:
- it's accessible from scripts, or udev rules
- the name is similar to what MD-RAID has
(/proc/sys/dev/raid/speed_limit_max or /sys/block/mdX/md/sync_speed_max)
- the value is sticky at least for filesystem mount time
- adjusting the value has immediate effect
- sysfs is available in constrained environments (eg. system rescue)
- the limit also applies to device replace
Sysfs:
- raw value is in bytes
- values written to the file accept suffixes like K, M
- file is in the per-device directory /sys/fs/btrfs/FSID/devinfo/DEVID/scrub_speed_max
- 0 means use default priority of IO
The scheduler is a simple deadline one and the accuracy is up to nearest
128K.
To be able to construct a zone append bio we need to look up the
btrfs_device. The code doing the chunk map lookup to get the device is
present in btrfs_submit_compressed_write and submit_extent_page.
Factor out the lookup calls into a helper and use it in the submission
paths.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Tian Tao [Wed, 5 May 2021 01:26:28 +0000 (09:26 +0800)]
btrfs: return EAGAIN if defrag is canceled
When inode defrag is canceled, the error is set to EAGAIN but then
overwritten by number of defragmented bytes. As this would hide the
error, rather return EAGAIN. This does not harm 'btrfs fi defrag', it
will print the error and continue to next file (as it does in for any
other error).
Signed-off-by: Tian Tao <tiantao6@hisilicon.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ update changelog ] Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Mon, 3 May 2021 02:08:56 +0000 (10:08 +0800)]
btrfs: remove io_failure_record::in_validation
The io_failure_record::in_validation was introduced to handle failed bio
which cross several sectors. In such case, we still need to verify
which sectors are corrupted.
But since we've changed the way how we handle corrupted sectors, by only
submitting repair for each corrupted sector, there is no need for extra
validation any more.
This patch will cleanup all io_failure_record::in_validation related
code.
Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Mon, 3 May 2021 02:08:55 +0000 (10:08 +0800)]
btrfs: submit read time repair only for each corrupted sector
Currently btrfs_submit_read_repair() has some extra check on whether the
failed bio needs extra validation for repair. But we can avoid all
these extra mechanisms if we submit the repair for each sector.
By this, each read repair can be easily handled without the need to
verify which sector is corrupted.
This will also benefit subpage, as one subpage bvec can contain several
sectors, making the extra verification more complex.
So this patch will:
- Introduce repair_one_sector()
The main code submitting repair, which is more or less the same as old
btrfs_submit_read_repair().
But this time, it only repairs one sector.
- Make btrfs_submit_read_repair() to handle sectors differently
There are 3 different cases:
* Good sector
We need to release the page and extent, set the range uptodate.
* Bad sector and failed to submit repair bio
We need to release the page and extent, but not set the range
uptodate.
* Bad sector but repair bio submitted
The page and extent release will be handled by the submitted repair
bio. Nothing needs to be done.
Since btrfs_submit_read_repair() will handle the page and extent
release now, we need to skip to next bvec even we hit some error.
- Change the lifespan of @uptodate in end_bio_extent_readpage()
Since now btrfs_submit_read_repair() will handle the full bvec
which contains any corruption, we don't need to bother updating
@uptodate bit anymore.
Just let @uptodate to be local variable inside the main loop,
so that any error from one bvec won't affect later bvec.
- Only export btrfs_repair_one_sector(), unexport
btrfs_submit_read_repair()
The only outside caller for read repair is DIO, which already submits
its repair for just one sector.
Only export btrfs_repair_one_sector() for DIO.
This patch will focus on the change on the repair path, the extra
validation code is still kept as is, and will be cleaned up later.
Signed-off-by: Qu Wenruo <wqu@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Qu Wenruo [Mon, 3 May 2021 02:08:54 +0000 (10:08 +0800)]
btrfs: make btrfs_verify_data_csum() to return a bitmap
This will provide the basis for later per-sector repair for subpage,
while still keeping the existing code happy.
As if all csums match, the return value will be 0, same as now.
Only when csum mismatches, the return value is different.
The new return value will be a bitmap, for 4K sectorsize and 4K page
size, it will be either 1, instead of the -EIO (which is not used
directly by the callers, no effective change).
But for 4K sectorsize and 64K page size, aka subpage case, since the
bvec can contain multiple sectors, knowing which sectors are corrupted
will allow us to submit repair only for corrupted sectors.
Signed-off-by: Qu Wenruo <wqu@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs: rename check_async_write and let it return bool
The 'check_async_write' function is a helper used in
'btrfs_submit_metadata_bio' and it checks if asynchronous writing can be
used for metadata.
Make the function return bool and get rid of the local variable async in
btrfs_submit_metadata_bio storing the result of check_async_write's
tests.
As this is touching all function call sites, also rename it to
should_async_write as this is more in line with the naming we use.
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs: zoned: bail out if we can't read a reliable write pointer
If we can't read a reliable write pointer from a sequential zone fail
creating the block group with an I/O error.
Also if the read write pointer is beyond the end of the respective zone,
fail the creation of the block group on this zone with an I/O error.
While this could also happen in real world scenarios with misbehaving
drives, this issue addresses a problem uncovered by fstests' test case
generic/475.
CC: stable@vger.kernel.org # 5.12+ Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs: zoned: print message when zone sanity check type fails
This extends patch 784daf2b9628 ("btrfs: zoned: sanity check zone
type"), the message was supposed to be there but was lost during merge.
We want to make the error noticeable so add it.
Fixes: 784daf2b9628 ("btrfs: zoned: sanity check zone type") CC: stable@vger.kernel.org # 5.12+ Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
If we decide to flush delalloc from the preemptive flusher, we really do
not want to wait on ordered extents, as it gains us nothing. However
there was logic to go ahead and wait on ordered extents if there was
more ordered bytes than delalloc bytes. We do not want this behavior,
so pass through whether this flushing is for preemption, and do not wait
for ordered extents if that's the case. Also break out of the shrink
loop after the first flushing, as we just want to one shot shrink
delalloc.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Wed, 28 Apr 2021 17:38:47 +0000 (13:38 -0400)]
btrfs: only ignore delalloc if delalloc is much smaller than ordered
While testing heavy delalloc workloads I noticed that sometimes we'd
just stop preemptively flushing when we had loads of delalloc available
to flush. This is because we skip preemptive flushing if delalloc <=
ordered. However if we start with say 4gib of delalloc, and we flush
2gib of that, we'll stop flushing there, when we still have 2gib of
delalloc to flush.
Instead adjust the ordered bytes down by half, this way if 2/3 of our
outstanding delalloc reservations are tied up by ordered extents we
don't bother preemptive flushing, as we're getting close to the state
where we need to wait on ordered extents.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Wed, 28 Apr 2021 17:38:46 +0000 (13:38 -0400)]
btrfs: don't include the global rsv size in the preemptive used amount
When deciding if we should preemptively flush space, we will add in the
amount of space used by all block rsvs. However this also includes the
global block rsv, which isn't flushable so shouldn't be accounted for in
this calculation. If we decide to use ->bytes_may_use in our used
calculation we need to subtract the global rsv size from this amount so
it most closely matches the flushable space.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Wed, 28 Apr 2021 17:38:45 +0000 (13:38 -0400)]
btrfs: use the global rsv size in the preemptive thresh calculation
We calculate the amount of "free" space available for normal
reservations by taking the total space and subtracting out the hard used
space, which is readonly, used, and reserved space.
However we weren't taking into account the global block rsv, which is
essentially hard used space. Handle this by subtracting it from the
available free space, so that our threshold more closely mirrors
reality.
We need to do the check because it's possible that the global_rsv_size +
used is > total_bytes, sometimes the global reserve can end up being
calculated as larger than the available size (think small filesystems
where we only have the original 8MiB chunk of metadata). It doesn't
usually happen, but that can get us into trouble so this is safer.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Wed, 28 Apr 2021 17:38:44 +0000 (13:38 -0400)]
btrfs: take into account global rsv in need_preemptive_reclaim
Global rsv can't be used for normal allocations, and for very full file
systems we can decide to try and async flush constantly even though
there's really not a lot of space to reclaim. Deal with this by
including the global block rsv size in the "total used" calculation.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Wed, 28 Apr 2021 17:38:43 +0000 (13:38 -0400)]
btrfs: only clamp the first time we have to start flushing
We were clamping the threshold for preemptive reclaim any time we added
a ticket to wait on, which if we have a lot of threads means we'd
essentially max out the clamp the first time we start to flush.
Instead of doing this, simply do it every time we have to start
flushing, this will make us ramp up gradually instead of going to max
clamping as soon as we start needing to do flushing.
Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
Josef Bacik [Wed, 28 Apr 2021 17:38:42 +0000 (13:38 -0400)]
btrfs: check worker before need_preemptive_reclaim
need_preemptive_reclaim() does some calculations, which aren't heavy,
but if we're already running preemptive reclaim there's no reason to do
them at all, so re-order the checks so that we don't do the calculation
if we're already doing reclaim.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Su Yue [Sun, 25 Apr 2021 08:35:04 +0000 (16:35 +0800)]
btrfs: remove stale comment for argument seed of btrfs_find_device
Commit b2598edf8b36 ("btrfs: remove unused argument seed from
btrfs_find_device") removed the argument seed from btrfs_find_device
but forgot the comment, so remove it.
Reviewed-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Su Yue <l@damenly.su> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
btrfs: correct try_lock_extent() usage in read_extent_buffer_subpage()
try_lock_extent() returns 1 on success or 0 for failure and not an error
code. If try_lock_extent() fails, read_extent_buffer_subpage() returns
zero indicating subpage extent read success.
Return EAGAIN/EWOULDBLOCK if try_lock_extent() fails in locking the
extent.
Reviewed-by: Qu Wenruo <wqu@suse.com> Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
Linus Torvalds [Sun, 20 Jun 2021 16:44:52 +0000 (09:44 -0700)]
Merge tag 'sched_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Borislav Petkov:
"A single fix to restore fairness between control groups with equal
priority"
* tag 'sched_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Correctly insert cfs_rq's to list on unthrottle
Linus Torvalds [Sun, 20 Jun 2021 16:38:14 +0000 (09:38 -0700)]
Merge tag 'irq_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Borislav Petkov:
"A single fix for GICv3 to not take an interrupt in an NMI context"
* tag 'irq_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3: Workaround inconsistent PMR setting on NMI entry
Linus Torvalds [Sun, 20 Jun 2021 16:09:58 +0000 (09:09 -0700)]
Merge tag 'x86_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Borislav Petkov:
"A first set of urgent fixes to the FPU/XSTATE handling mess^W code.
(There's a lot more in the pipe):
- Prevent corruption of the XSTATE buffer in signal handling by
validating what is being copied from userspace first.
- Invalidate other task's preserved FPU registers on XRSTOR failure
(#PF) because latter can still modify some of them.
- Restore the proper PKRU value in case userspace modified it
- Reset FPU state when signal restoring fails
Other:
- Map EFI boot services data memory as encrypted in a SEV guest so
that the guest can access it and actually boot properly
- Two SGX correctness fixes: proper resources freeing and a NUMA fix"
* tag 'x86_urgent_for_v5.13_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Avoid truncating memblocks for SGX memory
x86/sgx: Add missing xa_destroy() when virtual EPC is destroyed
x86/fpu: Reset state for all signal restore failures
x86/pkru: Write hardware init value to PKRU when xstate is init
x86/process: Check PF_KTHREAD and not current->mm for kernel threads
x86/fpu: Invalidate FPU state after a failed XRSTOR from a user buffer
x86/fpu: Prevent state corruption in __fpu__restore_sig()
x86/ioremap: Map EFI-reserved memory as encrypted for SEV
Linus Torvalds [Sat, 19 Jun 2021 23:50:23 +0000 (16:50 -0700)]
Merge tag 'powerpc-5.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc fixes from Michael Ellerman:
"Fix initrd corruption caused by our recent change to use relative jump
labels.
Fix a crash using perf record on systems without a hardware PMU
backend.
Rework our 64-bit signal handling slighty to make it more closely
match the old behaviour, after the recent change to use unsafe user
accessors.
Thanks to Anastasia Kovaleva, Athira Rajeev, Christophe Leroy, Daniel
Axtens, Greg Kurz, and Roman Bolshakov"
* tag 'powerpc-5.13-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/perf: Fix crash in perf_instruction_pointer() when ppmu is not set
powerpc: Fix initrd corruption with relative jump labels
powerpc/signal64: Copy siginfo before changing regs->nip
powerpc/mem: Add back missing header to fix 'no previous prototype' error
Linus Torvalds [Sat, 19 Jun 2021 21:50:43 +0000 (14:50 -0700)]
Merge tag 'perf-tools-fixes-for-v5.13-2021-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux
Pull perf tools fixes from Arnaldo Carvalho de Melo:
- Fix refcount usage when processing PERF_RECORD_KSYMBOL.
- 'perf stat' metric group fixes.
- Fix 'perf test' non-bash issue with stat bpf counters.
- Update unistd, in.h and socket.h with the kernel sources, silencing
perf build warnings.
* tag 'perf-tools-fixes-for-v5.13-2021-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
tools headers UAPI: Sync linux/in.h copy with the kernel sources
tools headers UAPI: Sync asm-generic/unistd.h with the kernel original
perf beauty: Update copy of linux/socket.h with the kernel sources
perf test: Fix non-bash issue with stat bpf counters
perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL
perf metricgroup: Return error code from metricgroup__add_metric_sys_event_iter()
perf metricgroup: Fix find_evsel_group() event selector
Linus Torvalds [Sat, 19 Jun 2021 15:45:34 +0000 (08:45 -0700)]
Merge tag 'riscv-for-linus-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:
- A build fix to always build modules with the 'medany' code model, as
the module loader doesn't support 'medlow'.
- A Kconfig warning fix for the SiFive errata.
- A pair of fixes that for regressions to the recent memory layout
changes.
- A fix for the FU740 device tree.
* tag 'riscv-for-linus-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: dts: fu740: fix cache-controller interrupts
riscv: Ensure BPF_JIT_REGION_START aligned with PMD size
riscv: kasan: Fix MODULES_VADDR evaluation due to local variables' name
riscv: sifive: fix Kconfig errata warning
riscv32: Use medany C model for modules
tools headers UAPI: Sync linux/in.h copy with the kernel sources
To pick the changes in:
321827477360934d ("icmp: don't send out ICMP messages with a source address of 0.0.0.0")
That don't result in any change in tooling, as INADDR_ are not used to
generate id->string tables used by 'perf trace'.
This addresses this build warning:
Warning: Kernel ABI header at 'tools/include/uapi/linux/in.h' differs from latest version at 'include/uapi/linux/in.h'
diff -u tools/include/uapi/linux/in.h include/uapi/linux/in.h
Cc: David S. Miller <davem@davemloft.net> Cc: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Those headers are used in some arches to generate the syscall table used
in 'perf trace' to translate syscall numbers into strings.
This addresses this perf build warning:
Warning: Kernel ABI header at 'tools/include/uapi/asm-generic/unistd.h' differs from latest version at 'include/uapi/asm-generic/unistd.h'
diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h
Cc: Jan Kara <jack@suse.cz> Cc: Marcin Juszkiewicz <marcin@juszkiewicz.com.pl> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
perf beauty: Update copy of linux/socket.h with the kernel sources
To pick the changes in:
ea6932d70e223e02 ("net: make get_net_ns return error if NET_NS is disabled")
That don't result in any changes in the tables generated from that
header.
This silences this perf build warning:
Warning: Kernel ABI header at 'tools/perf/trace/beauty/include/linux/socket.h' differs from latest version at 'include/linux/socket.h'
diff -u tools/perf/trace/beauty/include/linux/socket.h include/linux/socket.h
Cc: Changbin Du <changbin.du@intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Ian Rogers [Thu, 17 Jun 2021 18:42:13 +0000 (11:42 -0700)]
perf test: Fix non-bash issue with stat bpf counters
$(( .. )) is a bash feature but the test's interpreter is !/bin/sh,
switch the code to use expr.
Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <songliubraving@fb.com> Cc: bpf@vger.kernel.org Link: http://lore.kernel.org/lkml/20210617184216.2075588-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Riccardo Mancini [Sat, 12 Jun 2021 17:37:48 +0000 (19:37 +0200)]
perf machine: Fix refcount usage when processing PERF_RECORD_KSYMBOL
ASan reported a memory leak of BPF-related ksymbols map and dso. The
leak is caused by refount never reaching 0, due to missing __put calls
in the function machine__process_ksymbol_register.
Once the dso is inserted in the map, dso__put() should be called
(map__new2() increases the refcount to 2).
The same thing applies for the map when it's inserted into maps
(maps__insert() increases the refcount to 2).
$ sudo ./perf record -- sleep 5
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.025 MB perf.data (8 samples) ]
Direct leak of 6992 byte(s) in 19 object(s) allocated from:
#0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7)
#1 0x8e4e53 in map__new2 /home/user/linux/tools/perf/util/map.c:216:20
#2 0x8cf68c in machine__process_ksymbol_register /home/user/linux/tools/perf/util/machine.c:778:10
[...]
Indirect leak of 8702 byte(s) in 19 object(s) allocated from:
#0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7)
#1 0x8728d7 in dso__new_id /home/user/linux/tools/perf/util/dso.c:1256:20
#2 0x872015 in dso__new /home/user/linux/tools/perf/util/dso.c:1295:9
#3 0x8cf623 in machine__process_ksymbol_register /home/user/linux/tools/perf/util/machine.c:774:21
[...]
Indirect leak of 1520 byte(s) in 19 object(s) allocated from:
#0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7)
#1 0x87b3da in symbol__new /home/user/linux/tools/perf/util/symbol.c:269:23
#2 0x888954 in map__process_kallsym_symbol /home/user/linux/tools/perf/util/symbol.c:710:8
[...]
Indirect leak of 1406 byte(s) in 19 object(s) allocated from:
#0 0x4f43c7 in calloc (/home/user/linux/tools/perf/perf+0x4f43c7)
#1 0x87b3da in symbol__new /home/user/linux/tools/perf/util/symbol.c:269:23
#2 0x8cfbd8 in machine__process_ksymbol_register /home/user/linux/tools/perf/util/machine.c:803:8
[...]
Signed-off-by: Riccardo Mancini <rickyman7@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiapeng Chong <jiapeng.chong@linux.alibaba.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Tommi Rantala <tommi.t.rantala@nokia.com> Link: http://lore.kernel.org/lkml/20210612173751.188582-1-rickyman7@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
John Garry [Thu, 10 Jun 2021 14:33:00 +0000 (22:33 +0800)]
perf metricgroup: Return error code from metricgroup__add_metric_sys_event_iter()
The error code is not set at all in the sys event iter function.
This may lead to an uninitialized value of "ret" in
metricgroup__add_metric() when no CPU metric is added.
Fix by properly setting the error code.
It is not necessary to init "ret" to 0 in metricgroup__add_metric(), as
if we have no CPU or sys event metric matching, then "has_match" should
be 0 and "ret" is set to -EINVAL.
However gcc cannot detect that it may not have been set after the
map_for_each_metric() loop for CPU metrics, which is strange.
Fixes: be335ec28efa8 ("perf metricgroup: Support adding metrics for system PMUs") Signed-off-by: John Garry <john.garry@huawei.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/1623335580-187317-3-git-send-email-john.garry@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The following command segfaults on my x86 broadwell:
$ ./perf stat -M frontend_bound,retiring,backend_bound,bad_speculation sleep 1
WARNING: grouped events cpus do not match, disabling group:
anon group { raw 0x10e }
anon group { raw 0x10e }
perf: util/evsel.c:1596: get_group_fd: Assertion `!(!leader->core.fd)' failed.
Aborted (core dumped)
The issue shows itself as a use-after-free in evlist__check_cpu_maps(),
whereby the leader of an event selector (evsel) has been deleted (yet we
still attempt to verify for an evsel).
Fundamentally the problem comes from metricgroup__setup_events() ->
find_evsel_group(), and has developed from the previous fix attempt in
commit 9c880c24cb0d ("perf metricgroup: Fix for metrics containing
duration_time").
The problem now is that the logic in checking if an evsel is in the same
group is subtly broken for the "cycles" event. For the "cycles" event,
the pmu_name is NULL; however the logic in find_evsel_group() may set an
event matched against "cycles" as used, when it should not be.
This leads to a condition where an evsel is set, yet its leader is not.
Fix the check for evsel pmu_name by not matching evsels when either has a
NULL pmu_name.
There is still a pre-existing metric issue whereby the ordering of the
metrics may break the 'stat' function, as discussed at:
https://lore.kernel.org/lkml/49c6fccb-b716-1bf0-18a6-cace1cdb66b9@huawei.com/
Fixes: 9c880c24cb0d ("perf metricgroup: Fix for metrics containing duration_time") Signed-off-by: John Garry <john.garry@huawei.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> # On a Thinkpad T450S Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lore.kernel.org/lkml/1623335580-187317-2-git-send-email-john.garry@huawei.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Jisheng Zhang [Fri, 18 Jun 2021 14:09:13 +0000 (22:09 +0800)]
riscv: Ensure BPF_JIT_REGION_START aligned with PMD size
Andreas reported commit fc8504765ec5 ("riscv: bpf: Avoid breaking W^X")
breaks booting with one kind of defconfig, I reproduced a kernel panic
with the defconfig:
After some investigation, I think I found the root cause: commit 2bfc6cd81bd ("move kernel mapping outside of linear mapping") moves
BPF JIT region after the kernel:
The &_end is unlikely aligned with PMD size, so the front bpf jit
region sits with part of kernel .data section in one PMD size mapping.
But kernel is mapped in PMD SIZE, when bpf_jit_binary_lock_ro() is
called to make the first bpf jit prog ROX, we will make part of kernel
.data section RO too, so when we write to, for example memset the
.data section, MMU will trigger a store page fault.
To fix the issue, we need to ensure the BPF JIT region is PMD size
aligned. This patch acchieve this goal by restoring the BPF JIT region
to original position, I.E the 128MB before kernel .text section. The
modification to kasan_init.c is inspired by Alexandre.
Jisheng Zhang [Fri, 18 Jun 2021 14:01:36 +0000 (22:01 +0800)]
riscv: kasan: Fix MODULES_VADDR evaluation due to local variables' name
commit 2bfc6cd81bd1 ("riscv: Move kernel mapping outside of linear
mapping") makes use of MODULES_VADDR to populate kernel, BPF, modules
mapping. Currently, MODULES_VADDR is defined as below for RV64:
But kasan_init() has two local variables which are also named as _start,
_end, so MODULES_VADDR is evaluated with the local variable _end
rather than the global "_end" as we expected. Fix this issue by
renaming the two local variables.
Fixes: 2bfc6cd81bd1 ("riscv: Move kernel mapping outside of linear mapping") Signed-off-by: Jisheng Zhang <jszhang@kernel.org> Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Linus Torvalds [Fri, 18 Jun 2021 23:39:03 +0000 (16:39 -0700)]
Merge tag 'for-5.13-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fix from David Sterba:
"One more fix, for a space accounting bug in zoned mode. It happens
when a block group is switched back rw->ro and unusable bytes (due to
zoned constraints) are subtracted twice.
It has user visible effects so I consider it important enough for late
-rc inclusion and backport to stable"
* tag 'for-5.13-rc6-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: zoned: fix negative space_info->bytes_readonly
- Avoid secondary bus resets on TI KeyStone C667X devices (Antti
Järvinen)
- Avoid secondary bus resets on some NVIDIA GPUs (Shanker Donthineni)
- Work around FLR erratum on Huawei Intelligent NIC VF (Chiqijun)
- Avoid broken ATS on AMD Navi14 GPU (Evan Quan)
- Trust Broadcom BCM57414 NIC to isolate functions even though it
doesn't advertise ACS support (Sriharsha Basavapatna)
- Work around AMD RS690 BIOSes that don't configure DMA above 4GB
(Mikel Rychliski)
- Fix panic during PIO transfer on Aardvark controller (Pali Rohár)
* tag 'pci-v5.13-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: aardvark: Fix kernel panic during PIO transfer
PCI: Add AMD RS690 quirk to enable 64-bit DMA
PCI: Add ACS quirk for Broadcom BCM57414 NIC
PCI: Mark AMD Navi14 GPU ATS as broken
PCI: Work around Huawei Intelligent NIC VF FLR erratum
PCI: Mark some NVIDIA GPUs to avoid bus reset
PCI: Mark TI C667X to avoid bus reset
PCI: tegra194: Fix MCFG quirk build regressions
PCI: of: Clear 64-bit flag for non-prefetchable memory below 4GB
afs: Re-enable freezing once a page fault is interrupted
If a task is killed during a page fault, it does not currently call
sb_end_pagefault(), which means that the filesystem cannot be frozen
at any time thereafter. This may be reported by lockdep like this:
====================================
WARNING: fsstress/10757 still has locks held!
5.13.0-rc4-build4+ #91 Not tainted
------------------------------------
1 lock held by fsstress/10757:
#0: ffff888104eac530
(
sb_pagefaults
as filesystem freezing is modelled as a lock.
Fix this by removing all the direct returns from within the function,
and using 'ret' to indicate whether we were interrupted or successful.
priv is netdev private data, but it is used
after free_netdev(). It can cause use-after-free when accessing priv
pointer. So, fix it by moving free_netdev() after pci_iounmap()
calls.
Fixes: 6af55ff52b02 ("Driver for Beckhoff CX5020 EtherCAT master module.") Signed-off-by: Pavel Skripkin <paskripkin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 18 Jun 2021 19:22:55 +0000 (12:22 -0700)]
Merge tag 'mac80211-for-net-2021-06-18' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211
Johannes Berg says:
====================
A couple of straggler fixes:
* a minstrel HT sample check fix
* peer measurement could double-free on races
* certificate file generation at build time could
sometimes hang
* some parameters weren't reset between connections
in mac80211
* some extensible elements were treated as non-
extensible, possibly causuing bad connections
(or failures) if the AP adds data
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
selftests/net: Add icmp.sh for testing ICMP dummy address responses
This adds a new icmp.sh selftest for testing that the kernel will respond
correctly with an ICMP unreachable message with the dummy (192.0.0.8)
source address when there are no IPv4 addresses configured to use as source
addresses.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
icmp: don't send out ICMP messages with a source address of 0.0.0.0
When constructing ICMP response messages, the kernel will try to pick a
suitable source address for the outgoing packet. However, if no IPv4
addresses are configured on the system at all, this will fail and we end up
producing an ICMP message with a source address of 0.0.0.0. This can happen
on a box routing IPv4 traffic via v6 nexthops, for instance.
Since 0.0.0.0 is not generally routable on the internet, there's a good
chance that such ICMP messages will never make it back to the sender of the
original packet that the ICMP message was sent in response to. This, in
turn, can create connectivity and PMTUd problems for senders. Fortunately,
RFC7600 reserves a dummy address to be used as a source for ICMP
messages (192.0.0.8/32), so let's teach the kernel to substitute that
address as a last resort if the regular source address selection procedure
fails.
Below is a quick example reproducing this issue with network namespaces:
ip netns add ns0
ip l add type veth peer netns ns0
ip l set dev veth0 up
ip a add 10.0.0.1/24 dev veth0
ip a add fc00:dead:cafe:42::1/64 dev veth0
ip r add 10.1.0.0/24 via inet6 fc00:dead:cafe:42::2
ip -n ns0 l set dev veth0 up
ip -n ns0 a add fc00:dead:cafe:42::2/64 dev veth0
ip -n ns0 r add 10.0.0.0/24 via inet6 fc00:dead:cafe:42::1
ip netns exec ns0 sysctl -w net.ipv4.icmp_ratelimit=0
ip netns exec ns0 sysctl -w net.ipv4.ip_forward=1
tcpdump -tpni veth0 -c 2 icmp &
ping -w 1 10.1.0.1 > /dev/null
tcpdump: verbose output suppressed, use -v[v]... for full protocol decode
listening on veth0, link-type EN10MB (Ethernet), snapshot length 262144 bytes
IP 10.0.0.1 > 10.1.0.1: ICMP echo request, id 29, seq 1, length 64
IP 0.0.0.0 > 10.0.0.1: ICMP net 10.1.0.1 unreachable, length 92
2 packets captured
2 packets received by filter
0 packets dropped by kernel
With this patch the above capture changes to:
IP 10.0.0.1 > 10.1.0.1: ICMP echo request, id 31127, seq 1, length 64
IP 192.0.0.8 > 10.0.0.1: ICMP net 10.1.0.1 unreachable, length 92
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Reported-by: Juliusz Chroboczek <jch@irif.fr> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
As documented in Documentation/networking/driver.rst, the ndo_start_xmit
method must not return NETDEV_TX_BUSY under any normal circumstances, and
as recommended, we simply stop the tx queue in advance, when there is a
risk that the next xmit would cause a NETDEV_TX_BUSY return.
Signed-off-by: Esben Haabendal <esben@geanix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Esben Haabendal [Fri, 18 Jun 2021 10:52:33 +0000 (12:52 +0200)]
net: ll_temac: Fix TX BD buffer overwrite
Just as the initial check, we need to ensure num_frag+1 buffers available,
as that is the number of buffers we are going to use.
This fixes a buffer overflow, which might be seen during heavy network
load. Complete lockup of TEMAC was reproducible within about 10 minutes of
a particular load.
Fixes: 84823ff80f74 ("net: ll_temac: Fix race condition causing TX hang") Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Esben Haabendal <esben@geanix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Esben Haabendal [Fri, 18 Jun 2021 10:52:28 +0000 (12:52 +0200)]
net: ll_temac: Add memory-barriers for TX BD access
Add a couple of memory-barriers to ensure correct ordering of read/write
access to TX BDs.
In xmit_done, we should ensure that reading the additional BD fields are
only done after STS_CTRL_APP0_CMPLT bit is set.
When xmit_done marks the BD as free by setting APP0=0, we need to ensure
that the other BD fields are reset first, so we avoid racing with the xmit
path, which writes to the same fields.
Finally, making sure to read APP0 of next BD after the current BD, ensures
that we see all available buffers.
Signed-off-by: Esben Haabendal <esben@geanix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Esben Haabendal [Fri, 18 Jun 2021 10:52:23 +0000 (12:52 +0200)]
net: ll_temac: Make sure to free skb when it is completely used
With the skb pointer piggy-backed on the TX BD, we have a simple and
efficient way to free the skb buffer when the frame has been transmitted.
But in order to avoid freeing the skb while there are still fragments from
the skb in use, we need to piggy-back on the TX BD of the skb, not the
first.
Without this, we are doing use-after-free on the DMA side, when the first
BD of a multi TX BD packet is seen as completed in xmit_done, and the
remaining BDs are still being processed.
Cc: stable@vger.kernel.org # v5.4+ Signed-off-by: Esben Haabendal <esben@geanix.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Fri, 18 Jun 2021 19:00:27 +0000 (12:00 -0700)]
Merge branch 'bnxt_en-fixes'
Michael Chan says:
====================
bnxt_en: Bug fixes
This patchset includes 3 small bug fixes to reinitialize PHY capabilities
after firmware reset, setup the chip's internal TQM fastpath ring
backing memory properly for RoCE traffic, and to free ethtool related
memory if driver probe fails.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Somnath Kotur [Fri, 18 Jun 2021 06:07:27 +0000 (02:07 -0400)]
bnxt_en: Call bnxt_ethtool_free() in bnxt_init_one() error path
bnxt_ethtool_init() may have allocated some memory and we need to
call bnxt_ethtool_free() to properly unwind if bnxt_init_one()
fails.
Fixes: 7c3809181468 ("bnxt_en: Refactor bnxt_init_one() and turn on TPA support on 57500 chips.") Signed-off-by: Somnath Kotur <somnath.kotur@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Rukhsana Ansari [Fri, 18 Jun 2021 06:07:26 +0000 (02:07 -0400)]
bnxt_en: Fix TQM fastpath ring backing store computation
TQM fastpath ring needs to be sized to store both the requester
and responder side of RoCE QPs in TQM for supporting bi-directional
tests. Fix bnxt_alloc_ctx_mem() to multiply the RoCE QPs by a factor of
2 when computing the number of entries for TQM fastpath ring. This
fixes an RX pipeline stall issue when running bi-directional max
RoCE QP tests.
Fixes: c7dd7ab4b204 ("bnxt_en: Improve TQM ring context memory sizing formulas.") Signed-off-by: Rukhsana Ansari <rukhsana.ansari@broadcom.com> Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Fri, 18 Jun 2021 06:07:25 +0000 (02:07 -0400)]
bnxt_en: Rediscover PHY capabilities after firmware reset
There is a missing bnxt_probe_phy() call in bnxt_fw_init_one() to
rediscover the PHY capabilities after a firmware reset. This can cause
some PHY related functionalities to fail after a firmware reset. For
example, in multi-host, the ability for any host to configure the PHY
settings may be lost after a firmware reset.
Fixes: ec5d31e3c15d ("bnxt_en: Handle firmware reset status during IF_UP.") Signed-off-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Machek [Fri, 18 Jun 2021 09:29:48 +0000 (11:29 +0200)]
cxgb4: fix wrong shift.
While fixing coverity warning, commit dd2c79677375 introduced typo in
shift value. Fix that.
Signed-off-by: Pavel Machek (CIP) <pavel@denx.de> Fixes: dd2c79677375 ("cxgb4: Fix unintentional sign extension issues") Signed-off-by: David S. Miller <davem@davemloft.net>
Linus Torvalds [Fri, 18 Jun 2021 18:09:23 +0000 (11:09 -0700)]
Merge tag 'arc-5.13-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc
Pull ARC fixes from Vineet Gupta:
- ARCv2 userspace ABI not populating a few registers
- Unbork CONFIG_HARDENED_USERCOPY for ARC
* tag 'arc-5.13-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: fix CONFIG_HARDENED_USERCOPY
ARCv2: save ABI registers across signal handling
Linus Torvalds [Fri, 18 Jun 2021 17:57:09 +0000 (10:57 -0700)]
Merge tag 'trace-v5.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Have recordmcount check for valid st_shndx otherwise some archs may
have invalid references for the mcount location.
- Two fixes done for mapping pids to task names. Traces were not
showing the names of tasks when they should have.
- Fix to trace_clock_global() to prevent it from going backwards
* tag 'trace-v5.13-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Do no increment trace_clock_global() by one
tracing: Do not stop recording comms if the trace file is being read
tracing: Do not stop recording cmdlines when tracing is off
recordmcount: Correct st_shndx handling
Linus Torvalds [Fri, 18 Jun 2021 17:42:36 +0000 (10:42 -0700)]
Merge tag 'pm-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"Remove recently added frequency invariance support from the CPPC
cpufreq driver, because it has turned out to be problematic and it
cannot be fixed properly on time for 5.13 (Viresh Kumar)"
* tag 'pm-5.13-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
Revert "cpufreq: CPPC: Add support for frequency invariance"
Fan Du [Thu, 17 Jun 2021 19:46:57 +0000 (12:46 -0700)]
x86/mm: Avoid truncating memblocks for SGX memory
tl;dr:
Several SGX users reported seeing the following message on NUMA systems:
sgx: [Firmware Bug]: Unable to map EPC section to online node. Fallback to the NUMA node 0.
This turned out to be the memblock code mistakenly throwing away SGX
memory.
=== Full Changelog ===
The 'max_pfn' variable represents the highest known RAM address. It can
be used, for instance, to quickly determine for which physical addresses
there is mem_map[] space allocated. The numa_meminfo code makes an
effort to throw out ("trim") all memory blocks which are above 'max_pfn'.
SGX memory is not considered RAM (it is marked as "Reserved" in the
e820) and is not taken into account by max_pfn. Despite this, SGX memory
areas have NUMA affinity and are enumerated in the ACPI SRAT table. The
existing SGX code uses the numa_meminfo mechanism to look up the NUMA
affinity for its memory areas.
In cases where SGX memory was above max_pfn (usually just the one EPC
section in the last highest NUMA node), the numa_memblock is truncated
at 'max_pfn', which is below the SGX memory. When the SGX code tries to
look up the affinity of this memory, it fails and produces an error message:
sgx: [Firmware Bug]: Unable to map EPC section to online node. Fallback to the NUMA node 0.
and assigns the memory to NUMA node 0.
Instead of silently truncating the memory block at 'max_pfn' and
dropping the SGX memory, add the truncated portion to
'numa_reserved_meminfo'. This allows the SGX code to later determine
the NUMA affinity of its 'Reserved' area.
Before, numa_meminfo looked like this (from 'crash'):
blk = { start = 0x0, end = 0x2080000000, nid = 0x0 }
{ start = 0x2080000000, end = 0x4000000000, nid = 0x1 }
numa_reserved_meminfo is empty.
With this, numa_meminfo looks like this:
blk = { start = 0x0, end = 0x2080000000, nid = 0x0 }
{ start = 0x2080000000, end = 0x4000000000, nid = 0x1 }
and numa_reserved_meminfo has an entry for node 1's SGX memory:
blk = { start = 0x4000000000, end = 0x4080000000, nid = 0x1 }
[ daveh: completely rewrote/reworked changelog ]
Fixes: 5d30f92e7631 ("x86/NUMA: Provide a range-to-target_node lookup facility") Reported-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Fan Du <fan.du@intel.com> Signed-off-by: Dave Hansen <dave.hansen@intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org> Reviewed-by: Dan Williams <dan.j.williams@intel.com> Reviewed-by: Dave Hansen <dave.hansen@intel.com> Cc: <stable@vger.kernel.org> Link: https://lkml.kernel.org/r/20210617194657.0A99CB22@viggo.jf.intel.com
Linus Torvalds [Fri, 18 Jun 2021 17:36:18 +0000 (10:36 -0700)]
Merge tag 'drm-fixes-2021-06-18' of git://anongit.freedesktop.org/drm/drm
Pull drm fixes from Dave Airlie:
"Not much happening in fixes land this week only one PR for two amdgpu
powergating fixes was waiting for me, maybe something will show up
over the weekend, maybe not.
amdgpu:
- GFX9 and 10 powergating fixes"
* tag 'drm-fixes-2021-06-18' of git://anongit.freedesktop.org/drm/drm:
drm/amdgpu/gfx10: enlarge CP_MEC_DOORBELL_RANGE_UPPER to cover full doorbell.
drm/amdgpu/gfx9: fix the doorbell missing when in CGPG issue.
Pali Rohár [Tue, 8 Jun 2021 20:36:55 +0000 (22:36 +0200)]
PCI: aardvark: Fix kernel panic during PIO transfer
Trying to start a new PIO transfer by writing value 0 in PIO_START register
when previous transfer has not yet completed (which is indicated by value 1
in PIO_START) causes an External Abort on CPU, which results in kernel
panic:
SError Interrupt on CPU0, code 0xbf000002 -- SError
Kernel panic - not syncing: Asynchronous SError Interrupt
To prevent kernel panic, it is required to reject a new PIO transfer when
previous one has not finished yet.
If previous PIO transfer is not finished yet, the kernel may issue a new
PIO request only if the previous PIO transfer timed out.
In the past the root cause of this issue was incorrectly identified (as it
often happens during link retraining or after link down event) and special
hack was implemented in Trusted Firmware to catch all SError events in EL3,
to ignore errors with code 0xbf000002 and not forwarding any other errors
to kernel and instead throw panic from EL3 Trusted Firmware handler.
Links to discussion and patches about this issue:
https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/commit/?id=3c7dcdac5c50
https://lore.kernel.org/linux-pci/20190316161243.29517-1-repk@triplefau.lt/
https://lore.kernel.org/linux-pci/971be151d24312cc533989a64bd454b4@www.loen.fr/
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/1541
But the real cause was the fact that during link retraining or after link
down event the PIO transfer may take longer time, up to the 1.44s until it
times out. This increased probability that a new PIO transfer would be
issued by kernel while previous one has not finished yet.
After applying this change into the kernel, it is possible to revert the
mentioned TF-A hack and SError events do not have to be caught in TF-A EL3.
Link: https://lore.kernel.org/r/20210608203655.31228-1-pali@kernel.org Signed-off-by: Pali Rohár <pali@kernel.org> Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Marek Behún <kabel@kernel.org> Cc: stable@vger.kernel.org # 7fbcb5da811b ("PCI: aardvark: Don't rely on jiffies while holding spinlock")
Other drivers required by this mainboard either don't support 64-bit DMA,
or have it disabled using driver specific quirks. For example, the ahci
driver has quirks to enable or disable 64-bit DMA depending on the BIOS
version (see ahci_sb600_enable_64bit() in ahci.c). This ahci quirk matches
against the SB600 SATA controller, but the real issue is almost certainly
with the RS690 PCI host that it was commonly attached to.
To avoid this issue in all drivers with 64-bit DMA support, fix the
configuration of the PCI host. If the kernel is aware of physical memory
above 4GB, but the BIOS never configured the PCI host with this
information, update the registers with our values.
The Broadcom BCM57414 NIC may be a multi-function device. While it does
not advertise an ACS capability, peer-to-peer transactions are not possible
between the individual functions, so it is safe to treat them as fully
isolated.
Add an ACS quirk for this device so the functions can be in independent
IOMMU groups and attached individually to userspace applications using
VFIO.
Evan Quan [Wed, 2 Jun 2021 02:12:55 +0000 (10:12 +0800)]
PCI: Mark AMD Navi14 GPU ATS as broken
Observed unexpected GPU hang during runpm stress test on 0x7341 rev 0x00.
Further debugging shows broken ATS is related.
Disable ATS on this part. Similar issues on other devices:
a2da5d8cc0b0 ("PCI: Mark AMD Raven iGPU ATS as broken in some platforms") 45beb31d3afb ("PCI: Mark AMD Navi10 GPU rev 0x00 ATS as broken") 5e89cd303e3a ("PCI: Mark AMD Navi14 GPU rev 0xc5 ATS as broken")
Suggested-by: Alex Deucher <alexander.deucher@amd.com> Link: https://lore.kernel.org/r/20210602021255.939090-1-evan.quan@amd.com Signed-off-by: Evan Quan <evan.quan@amd.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Krzysztof Wilczyński <kw@linux.com> Cc: stable@vger.kernel.org
Chiqijun [Mon, 24 May 2021 22:44:07 +0000 (17:44 -0500)]
PCI: Work around Huawei Intelligent NIC VF FLR erratum
pcie_flr() starts a Function Level Reset (FLR), waits 100ms (the maximum
time allowed for FLR completion by PCIe r5.0, sec 6.6.2), and waits for the
FLR to complete. It assumes the FLR is complete when a config read returns
valid data.
When we do an FLR on several Huawei Intelligent NIC VFs at the same time,
firmware on the NIC processes them serially. The VF may respond to config
reads before the firmware has completed its reset processing. If we bind a
driver to the VF (e.g., by assigning the VF to a virtual machine) in the
interval between the successful config read and completion of the firmware
reset processing, the NIC VF driver may fail to load.
Prevent this driver failure by waiting for the NIC firmware to complete its
reset processing. Not all NIC firmware supports this feature.
Some NVIDIA GPU devices do not work with SBR. Triggering SBR leaves the
device inoperable for the current system boot. It requires a system
hard-reboot to get the GPU device back to normal operating condition
post-SBR. For the affected devices, enable NO_BUS_RESET quirk to avoid the
issue.
This issue will be fixed in the next generation of hardware.
Antti Järvinen [Mon, 15 Mar 2021 10:26:06 +0000 (10:26 +0000)]
PCI: Mark TI C667X to avoid bus reset
Some TI KeyStone C667X devices do not support bus/hot reset. The PCIESS
automatically disables LTSSM when Secondary Bus Reset is received and
device stops working. Prevent bus reset for these devices. With this
change, the device can be assigned to VMs with VFIO, but it will leak state
between VMs.
Reference: https://e2e.ti.com/support/processors/f/791/t/954382 Link: https://lore.kernel.org/r/20210315102606.17153-1-antti.jarvinen@gmail.com Signed-off-by: Antti Järvinen <antti.jarvinen@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Kishon Vijay Abraham I <kishon@ti.com> Cc: stable@vger.kernel.org
Jon Hunter [Thu, 10 Jun 2021 06:41:34 +0000 (07:41 +0100)]
PCI: tegra194: Fix MCFG quirk build regressions
7f100744749e ("PCI: tegra: Add Tegra194 MCFG quirks for ECAM errata")
caused a few build regressions:
- 7f100744749e removed the Makefile rule for CONFIG_PCIE_TEGRA194, so
pcie-tegra.c can no longer be built as a module. Restore that rule.
- 7f100744749e added "#ifdef CONFIG_PCIE_TEGRA194" around the native
driver, but that's only set when the driver is built-in (for a module,
CONFIG_PCIE_TEGRA194_MODULE is defined).
The ACPI quirk is completely independent of the rest of the native
driver, so move the quirk to its own file and remove the #ifdef in the
native driver.
- 7f100744749e added symbols that are always defined but used only when
CONFIG_PCIEASPM, which causes warnings when CONFIG_PCIEASPM is not set:
drivers/pci/controller/dwc/pcie-tegra194.c:259:18: warning: ‘event_cntr_data_offset’ defined but not used [-Wunused-const-variable=]
drivers/pci/controller/dwc/pcie-tegra194.c:250:18: warning: ‘event_cntr_ctrl_offset’ defined but not used [-Wunused-const-variable=]
drivers/pci/controller/dwc/pcie-tegra194.c:243:27: warning: ‘pcie_gen_freq’ defined but not used [-Wunused-const-variable=]
Punit Agrawal [Mon, 14 Jun 2021 23:04:57 +0000 (08:04 +0900)]
PCI: of: Clear 64-bit flag for non-prefetchable memory below 4GB
Alexandru and Qu reported this resource allocation failure on ROCKPro64 v2
and ROCK Pi 4B, both based on the RK3399:
pci_bus 0000:00: root bus resource [mem 0xfa000000-0xfbdfffff 64bit]
pci 0000:00:00.0: PCI bridge to [bus 01]
pci 0000:00:00.0: BAR 14: no space for [mem size 0x00100000]
pci 0000:01:00.0: reg 0x10: [mem 0x00000000-0x00003fff 64bit]
"BAR 14" is the PCI bridge's 32-bit non-prefetchable window, and our PCI
allocation code isn't smart enough to allocate it in a host bridge window
marked as 64-bit, even though this should work fine.
A DT host bridge description includes the windows from the CPU address
space to the PCI bus space. On a few architectures (microblaze, powerpc,
sparc), the DT may also describe PCI devices themselves, including their
BARs.
Before 9d57e61bf723 ("of/pci: Add IORESOURCE_MEM_64 to resource flags for
64-bit memory addresses"), of_bus_pci_get_flags() ignored the fact that
some DT addresses described 64-bit windows and BARs. That was a problem
because the virtio virtual NIC has a 32-bit BAR and a 64-bit BAR, and the
driver couldn't distinguish them.
9d57e61bf723 set IORESOURCE_MEM_64 for those 64-bit DT ranges, which fixed
the virtio driver. But it also set IORESOURCE_MEM_64 for host bridge
windows, which exposed the fact that the PCI allocator isn't smart enough
to put 32-bit resources in those 64-bit windows.
Clear IORESOURCE_MEM_64 from host bridge windows since we don't need that
information.
tracing: Do no increment trace_clock_global() by one
The trace_clock_global() tries to make sure the events between CPUs is
somewhat in order. A global value is used and updated by the latest read
of a clock. If one CPU is ahead by a little, and is read by another CPU, a
lock is taken, and if the timestamp of the other CPU is behind, it will
simply use the other CPUs timestamp.
The lock is also only taken with a "trylock" due to tracing, and strange
recursions can happen. The lock is not taken at all in NMI context.
In the case where the lock is not able to be taken, the non synced
timestamp is returned. But it will not be less than the saved global
timestamp.
The problem arises because when the time goes "backwards" the time
returned is the saved timestamp plus 1. If the lock is not taken, and the
plus one to the timestamp is returned, there's a small race that can cause
the time to go backwards!
The above case shows to reads of trace_clock_global() on the same CPU, but
the second read returns one less than the first read. That is, time when
backwards, and this is not what is allowed by trace_clock_global().
This was triggered by heavy tracing and the ring buffer checker that tests
for the clock going backwards:
This happened more than once, and always for an off by one result. It also
started happening after commit aafe104aa9096 was added.
Cc: stable@vger.kernel.org Fixes: aafe104aa9096 ("tracing: Restructure trace_clock_global() to never block") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Do not stop recording comms if the trace file is being read
A while ago, when the "trace" file was opened, tracing was stopped, and
code was added to stop recording the comms to saved_cmdlines, for mapping
of the pids to the task name.
Code has been added that only records the comm if a trace event occurred,
and there's no reason to not trace it if the trace file is opened.
Cc: stable@vger.kernel.org Fixes: 7ffbd48d5cab2 ("tracing: Cache comms only after an event occurred") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing: Do not stop recording cmdlines when tracing is off
The saved_cmdlines is used to map pids to the task name, such that the
output of the tracing does not just show pids, but also gives a human
readable name for the task.
If the name is not mapped, the output looks like this:
<...>-1316 [005] ...2 132.044039: ...
Instead of this:
gnome-shell-1316 [005] ...2 132.044039: ...
The names are updated when tracing is running, but are skipped if tracing
is stopped. Unfortunately, this stops the recording of the names if the
top level tracer is stopped, and not if there's other tracers active.
The recording of a name only happens when a new event is written into a
ring buffer, so there is no need to test if tracing is on or not. If
tracing is off, then no event is written and no need to test if tracing is
off or not.
Remove the check, as it hides the names of tasks for events in the
instance buffers.
Cc: stable@vger.kernel.org Fixes: 7ffbd48d5cab2 ("tracing: Cache comms only after an event occurred") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
projects / kernel.git / log