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The PCI/TPH driver fiddles with the MSI-X control word of an active
interrupt completely unserialized against concurrent operations issued
from the interrupt core. It also brings the PCI/MSI-X internal cached
control word out of sync.
Provide a function, which has the required serialization and keeps the
control word cache in sync.
Unfortunately this requires to look up and lock the interrupt descriptor,
which should be only done in the interrupt core code. But confining this
particular oddity in the PCI/MSI core is the lesser of all evil. A
interrupt core implementation would require a larger pile of infrastructure
and indirections for dubious value.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/all/20250313130321.822790423@linutronix.de
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Convert the code to use the new guard(msi_descs_lock).
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/all/20250313130321.758905320@linutronix.de
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Convert the code to use the new guard(msi_descs_lock).
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/all/20250313130321.695027112@linutronix.de
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Convert the code to use the new guard(msi_descs_lock).
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/all/20250313130321.631772601@linutronix.de
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Convert the code to use the new guard(msi_descs_lock).
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Nishanth Menon <nm@ti.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Dhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/all/20250313130321.568379110@linutronix.de
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Provide a lock guard for MSI descriptor locking and update the core code
accordingly.
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/all/20250313130321.506045185@linutronix.de
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In cases where an allocation is consumed by another function, the
allocation needs to be retained on success or freed on failure. The code
pattern is usually:
struct foo *f = kzalloc(sizeof(*f), GFP_KERNEL);
struct bar *b;
,,,
// Initialize f
...
if (ret)
goto free;
...
bar = bar_create(f);
if (!bar) {
ret = -ENOMEM;
goto free;
}
...
return 0;
free:
kfree(f);
return ret;
This prevents using __free(kfree) on @f because there is no canonical way
to tell the cleanup code that the allocation should not be freed.
Abusing no_free_ptr() by force ignoring the return value is not really a
sensible option either.
Provide an explicit macro retain_ptr(), which NULLs the cleanup
pointer. That makes it easy to analyze and reason about.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/all/20250313130321.442025758@linutronix.de
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Fix memory corruption due to incorrect parameter being passed to bio_init
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: stable@vger.kernel.org # v6.5+
Fixes: 1d9a94389853 ("dm flakey: clone pages on write bio before corrupting them")
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gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs fixes from Christian Brauner:
- Bring in an RCU pathwalk fix for afs. This is brought in as a merge
from the vfs-6.15.shared.afs branch that needs this commit and other
trees already depend on it.
- Fix vboxfs unterminated string handling.
* tag 'vfs-6.14-rc7.fixes' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs:
vboxsf: Add __nonstring annotations for unterminated strings
afs: Fix afs_atcell_get_link() to handle RCU pathwalk
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Current minimum required version of binutils is 2.25, which
supports XSAVE{,OPT,C,S} and XRSTOR{,S} instruction mnemonics.
Replace the byte-wise specification of XSAVE{,OPT,C,S}
and XRSTOR{,S} with these proper mnemonics.
No functional change intended.
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/r/20250313130251.383204-1-ubizjak@gmail.com
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This improves the failure output by pointing to the failing line at the
top level of the test, e.g.:
# test_number: EXPECTATION FAILED at lib/printf_kunit.c:103
lib/printf_kunit.c:167: vsnprintf(buf, 256, "%#-12x", ...) wrote '0x1234abcd ', expected '0x1234abce '
# test_number: EXPECTATION FAILED at lib/printf_kunit.c:142
lib/printf_kunit.c:167: kvasprintf(..., "%#-12x", ...) returned '0x1234abcd ', expected '0x1234abce '
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250307-printf-kunit-convert-v6-3-4d85c361c241@gmail.com
Signed-off-by: Kees Cook <kees@kernel.org>
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Move all tests into `printf_test_cases`. This gives us nicer output in
the event of a failure.
Combine `plain_format` and `plain_hash` into `hash_pointer` since
they're testing the same scenario.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250307-printf-kunit-convert-v6-2-4d85c361c241@gmail.com
Signed-off-by: Kees Cook <kees@kernel.org>
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Convert the printf() self-test to a KUnit test.
In the interest of keeping the patch reasonably-sized this doesn't
refactor the tests into proper parameterized tests - it's all one big
test case.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20250307-printf-kunit-convert-v6-1-4d85c361c241@gmail.com
Signed-off-by: Kees Cook <kees@kernel.org>
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To permit the EFI stub to call this code even when building the kernel
without the legacy decompressor, move the trampoline out of the latter's
startup code.
This is part of an ongoing WIP effort on my part to make the existing,
generic EFI zboot format work on x86 as well.
No functional change intended.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250313120324.1095968-2-ardb+git@google.com
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scx_bpf_reenqueue_local() can be invoked from ops.cpu_release() to give
tasks that are queued to the local DSQ a chance to migrate to other
CPUs, when a CPU is taken by a higher scheduling class.
However, there is no point re-enqueuing tasks that can only run on that
particular CPU, as they would simply be re-added to the same local DSQ
without any benefit.
Therefore, skip per-CPU tasks in scx_bpf_reenqueue_local().
Signed-off-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
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steal the (clever) algorithm from get_random_u32_below()
this fixes a bug where we were passing roundup_pow_of_two() a 64 bit
number - we're squaring device latencies now:
[ +1.681698] ------------[ cut here ]------------
[ +0.000010] UBSAN: shift-out-of-bounds in ./include/linux/log2.h:57:13
[ +0.000011] shift exponent 64 is too large for 64-bit type 'long unsigned int'
[ +0.000011] CPU: 1 UID: 0 PID: 196 Comm: kworker/u32:13 Not tainted 6.14.0-rc6-dave+ #10
[ +0.000012] Hardware name: ASUS System Product Name/PRIME B460I-PLUS, BIOS 1301 07/13/2021
[ +0.000005] Workqueue: events_unbound __bch2_read_endio [bcachefs]
[ +0.000354] Call Trace:
[ +0.000005] <TASK>
[ +0.000007] dump_stack_lvl+0x5d/0x80
[ +0.000018] ubsan_epilogue+0x5/0x30
[ +0.000008] __ubsan_handle_shift_out_of_bounds.cold+0x61/0xe6
[ +0.000011] bch2_rand_range.cold+0x17/0x20 [bcachefs]
[ +0.000231] bch2_bkey_pick_read_device+0x547/0x920 [bcachefs]
[ +0.000229] __bch2_read_extent+0x1e4/0x18e0 [bcachefs]
[ +0.000241] ? bch2_btree_iter_peek_slot+0x3df/0x800 [bcachefs]
[ +0.000180] ? bch2_read_retry_nodecode+0x270/0x330 [bcachefs]
[ +0.000230] bch2_read_retry_nodecode+0x270/0x330 [bcachefs]
[ +0.000230] bch2_rbio_retry+0x1fa/0x600 [bcachefs]
[ +0.000224] ? bch2_printbuf_make_room+0x71/0xb0 [bcachefs]
[ +0.000243] ? bch2_read_csum_err+0x4a4/0x610 [bcachefs]
[ +0.000278] bch2_read_csum_err+0x4a4/0x610 [bcachefs]
[ +0.000227] ? __bch2_read_endio+0x58b/0x870 [bcachefs]
[ +0.000220] __bch2_read_endio+0x58b/0x870 [bcachefs]
[ +0.000268] ? try_to_wake_up+0x31c/0x7f0
[ +0.000011] ? process_one_work+0x176/0x330
[ +0.000008] process_one_work+0x176/0x330
[ +0.000008] worker_thread+0x252/0x390
[ +0.000008] ? __pfx_worker_thread+0x10/0x10
[ +0.000006] kthread+0xec/0x230
[ +0.000011] ? __pfx_kthread+0x10/0x10
[ +0.000009] ret_from_fork+0x31/0x50
[ +0.000009] ? __pfx_kthread+0x10/0x10
[ +0.000008] ret_from_fork_asm+0x1a/0x30
[ +0.000012] </TASK>
[ +0.000046] ---[ end trace ]---
Reported-by: Roland Vet <vet.roland@protonmail.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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get_random_u32_below() has a better algorithm than bch2_rand_range(),
it just didn't exist at the time.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
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Pull NVMe fixes from Keith:
"nvme fixes for Linux 6.14
- Concurrent pci error and hotplug handling fix (Keith)
- Endpoint function fixes (Damien)"
* tag 'nvme-6.14-2025-03-13' of git://git.infradead.org/nvme:
nvmet: pci-epf: Do not add an IRQ vector if not needed
nvmet: pci-epf: Set NVMET_PCI_EPF_Q_LIVE when a queue is fully created
nvme-pci: fix stuck reset on concurrent DPC and HP
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This reverts commit fac84846a28c0950d4433118b3dffd44306df62d.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250312073852.2123409-7-amir73il@gmail.com
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This reverts commit 20bf82a898b65c129af76deb96a1b415d3098a28.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250312073852.2123409-6-amir73il@gmail.com
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This reverts commit 8392bc2ff8c8bf7c4c5e6dfa71ccd893a3c046f6.
In the use case of buffered write whose input buffer is mmapped file on a
filesystem with a pre-content mark, the prefaulting of the buffer can
happen under the filesystem freeze protection (obtained in vfs_write())
which breaks assumptions of pre-content hook and introduces potential
deadlock of HSM handler in userspace with filesystem freezing.
Now that we have pre-content hooks at file mmap() time, disable the
pre-content event hooks on page fault to avoid the potential deadlock.
Reported-by: syzbot+7229071b47908b19d5b7@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-fsdevel/7ehxrhbvehlrjwvrduoxsao5k3x4aw275patsb3krkwuq573yv@o2hskrfawbnc/
Fixes: 8392bc2ff8c8 ("fsnotify: generate pre-content permission event on page fault")
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250312073852.2123409-5-amir73il@gmail.com
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This reverts commit 7f4796a46571ced5d3d5b0942e1bfea1eedaaecd.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250312073852.2123409-4-amir73il@gmail.com
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This reverts commit bb480760ffc7018e21ee6f60241c2b99ff26ee0e.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250312073852.2123409-3-amir73il@gmail.com
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git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:
====================
Netfilter/IPVS fixes for net
The following patchset contains Netfilter/IPVS fixes for net:
1) Missing initialization of cpu and jiffies32 fields in conncount,
from Kohei Enju.
2) Skip several tests in case kernel is tainted, otherwise tests bogusly
report failure too as they also check for tainted kernel,
from Florian Westphal.
3) Fix a hyphothetical integer overflow in do_ip_vs_get_ctl() leading
to bogus error logs, from Dan Carpenter.
4) Fix incorrect offset in ipv4 option match in nft_exthdr, from
Alexey Kashavkin.
netfilter pull request 25-03-13
* tag 'nf-25-03-13' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
netfilter: nft_exthdr: fix offset with ipv4_find_option()
ipvs: prevent integer overflow in do_ip_vs_get_ctl()
selftests: netfilter: skip br_netfilter queue tests if kernel is tainted
netfilter: nf_conncount: Fully initialize struct nf_conncount_tuple in insert_tree()
====================
Link: https://patch.msgid.link/20250313095636.2186-1-pablo@netfilter.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
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Fix a bug in match_session() that can causes the session to not be
reused in some cases.
Reproduction steps:
mount.cifs //server/share /mnt/a -o credentials=creds
mount.cifs //server/share /mnt/b -o credentials=creds,sec=ntlmssp
cat /proc/fs/cifs/DebugData | grep SessionId | wc -l
mount.cifs //server/share /mnt/b -o credentials=creds,sec=ntlmssp
mount.cifs //server/share /mnt/a -o credentials=creds
cat /proc/fs/cifs/DebugData | grep SessionId | wc -l
Cc: stable@vger.kernel.org
Reviewed-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Henrique Carvalho <henrique.carvalho@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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User-provided mount parameter closetimeo of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 5efdd9122eff ("smb3: allow deferred close timeout to be configurable")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
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User-provided mount parameter actimeo of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 6d20e8406f09 ("cifs: add attribute cache timeout (actimeo) tunable")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
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User-provided mount parameter acdirmax of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 4c9f948142a5 ("cifs: Add new mount parameter "acdirmax" to allow caching directory metadata")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
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User-provided mount parameter acregmax of type u32 is intended to have
an upper limit, but before it is validated, the value is converted from
seconds to jiffies which can lead to an integer overflow.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 5780464614f6 ("cifs: Add new parameter "acregmax" for distinct file and directory metadata timeout")
Signed-off-by: Murad Masimov <m.masimov@mt-integration.ru>
Signed-off-by: Steve French <stfrench@microsoft.com>
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When mounting a CIFS share with 'guest' mount option, mount.cifs(8)
will set empty password= and password2= options. Currently we only
handle empty strings from user= and password= options, so the mount
will fail with
cifs: Bad value for 'password2'
Fix this by handling empty string from password2= option as well.
Link: https://bbs.archlinux.org/viewtopic.php?id=303927
Reported-by: Adam Williamson <awilliam@redhat.com>
Closes: https://lore.kernel.org/r/83c00b5fea81c07f6897a5dd3ef50fd3b290f56c.camel@redhat.com
Fixes: 35f834265e0d ("smb3: fix broken reconnect when password changing on the server by allowing password rotation")
Cc: stable@vger.kernel.org
Signed-off-by: Paulo Alcantara (Red Hat) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
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amd_pmf_get_slider_info() checks the current profile to report correct
value to the TA inputs. If hidden options are in use then the wrong
values will be reported to TA.
Add the two compat options PLATFORM_PROFILE_BALANCED_PERFORMANCE and
PLATFORM_PROFILE_QUIET for this use.
Reported-by: Yijun Shen <Yijun.Shen@dell.com>
Fixes: 9a43102daf64d ("platform/x86/amd: pmf: Add balanced-performance to hidden choices")
Fixes: 44e94fece5170 ("platform/x86/amd: pmf: Add 'quiet' to hidden choices")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Acked-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20250306034402.50478-1-superm1@kernel.org
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
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Due to asynchronous driver probing there is a chance that the dummy
regulator hasn't already been probed when first accessing it.
Cc: stable@vger.kernel.org
Signed-off-by: Christian Eggers <ceggers@arri.de>
Link: https://patch.msgid.link/20250313103051.32430-3-ceggers@arri.de
Signed-off-by: Mark Brown <broonie@kernel.org>
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None of these functions are used outside of the MSI core.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250309084110.204054172@linutronix.de
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When on a MANA VM hibernation is triggered, as part of hibernate_snapshot(),
mana_gd_suspend() and mana_gd_resume() are called. If during this
mana_gd_resume(), a failure occurs with HWC creation, mana_port_debugfs
pointer does not get reinitialized and ends up pointing to older,
cleaned-up dentry.
Further in the hibernation path, as part of power_down(), mana_gd_shutdown()
is triggered. This call, unaware of the failures in resume, tries to cleanup
the already cleaned up mana_port_debugfs value and hits the following bug:
[ 191.359296] mana 7870:00:00.0: Shutdown was called
[ 191.359918] BUG: kernel NULL pointer dereference, address: 0000000000000098
[ 191.360584] #PF: supervisor write access in kernel mode
[ 191.361125] #PF: error_code(0x0002) - not-present page
[ 191.361727] PGD 1080ea067 P4D 0
[ 191.362172] Oops: Oops: 0002 [#1] SMP NOPTI
[ 191.362606] CPU: 11 UID: 0 PID: 1674 Comm: bash Not tainted 6.14.0-rc5+ #2
[ 191.363292] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS Hyper-V UEFI Release v4.1 11/21/2024
[ 191.364124] RIP: 0010:down_write+0x19/0x50
[ 191.364537] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 53 48 89 fb e8 de cd ff ff 31 c0 ba 01 00 00 00 <f0> 48 0f b1 13 75 16 65 48 8b 05 88 24 4c 6a 48 89 43 08 48 8b 5d
[ 191.365867] RSP: 0000:ff45fbe0c1c037b8 EFLAGS: 00010246
[ 191.366350] RAX: 0000000000000000 RBX: 0000000000000098 RCX: ffffff8100000000
[ 191.366951] RDX: 0000000000000001 RSI: 0000000000000064 RDI: 0000000000000098
[ 191.367600] RBP: ff45fbe0c1c037c0 R08: 0000000000000000 R09: 0000000000000001
[ 191.368225] R10: ff45fbe0d2b01000 R11: 0000000000000008 R12: 0000000000000000
[ 191.368874] R13: 000000000000000b R14: ff43dc27509d67c0 R15: 0000000000000020
[ 191.369549] FS: 00007dbc5001e740(0000) GS:ff43dc663f380000(0000) knlGS:0000000000000000
[ 191.370213] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 191.370830] CR2: 0000000000000098 CR3: 0000000168e8e002 CR4: 0000000000b73ef0
[ 191.371557] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 191.372192] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 191.372906] Call Trace:
[ 191.373262] <TASK>
[ 191.373621] ? show_regs+0x64/0x70
[ 191.374040] ? __die+0x24/0x70
[ 191.374468] ? page_fault_oops+0x290/0x5b0
[ 191.374875] ? do_user_addr_fault+0x448/0x800
[ 191.375357] ? exc_page_fault+0x7a/0x160
[ 191.375971] ? asm_exc_page_fault+0x27/0x30
[ 191.376416] ? down_write+0x19/0x50
[ 191.376832] ? down_write+0x12/0x50
[ 191.377232] simple_recursive_removal+0x4a/0x2a0
[ 191.377679] ? __pfx_remove_one+0x10/0x10
[ 191.378088] debugfs_remove+0x44/0x70
[ 191.378530] mana_detach+0x17c/0x4f0
[ 191.378950] ? __flush_work+0x1e2/0x3b0
[ 191.379362] ? __cond_resched+0x1a/0x50
[ 191.379787] mana_remove+0xf2/0x1a0
[ 191.380193] mana_gd_shutdown+0x3b/0x70
[ 191.380642] pci_device_shutdown+0x3a/0x80
[ 191.381063] device_shutdown+0x13e/0x230
[ 191.381480] kernel_power_off+0x35/0x80
[ 191.381890] hibernate+0x3c6/0x470
[ 191.382312] state_store+0xcb/0xd0
[ 191.382734] kobj_attr_store+0x12/0x30
[ 191.383211] sysfs_kf_write+0x3e/0x50
[ 191.383640] kernfs_fop_write_iter+0x140/0x1d0
[ 191.384106] vfs_write+0x271/0x440
[ 191.384521] ksys_write+0x72/0xf0
[ 191.384924] __x64_sys_write+0x19/0x20
[ 191.385313] x64_sys_call+0x2b0/0x20b0
[ 191.385736] do_syscall_64+0x79/0x150
[ 191.386146] ? __mod_memcg_lruvec_state+0xe7/0x240
[ 191.386676] ? __lruvec_stat_mod_folio+0x79/0xb0
[ 191.387124] ? __pfx_lru_add+0x10/0x10
[ 191.387515] ? queued_spin_unlock+0x9/0x10
[ 191.387937] ? do_anonymous_page+0x33c/0xa00
[ 191.388374] ? __handle_mm_fault+0xcf3/0x1210
[ 191.388805] ? __count_memcg_events+0xbe/0x180
[ 191.389235] ? handle_mm_fault+0xae/0x300
[ 191.389588] ? do_user_addr_fault+0x559/0x800
[ 191.390027] ? irqentry_exit_to_user_mode+0x43/0x230
[ 191.390525] ? irqentry_exit+0x1d/0x30
[ 191.390879] ? exc_page_fault+0x86/0x160
[ 191.391235] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[ 191.391745] RIP: 0033:0x7dbc4ff1c574
[ 191.392111] Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89
[ 191.393412] RSP: 002b:00007ffd95a23ab8 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
[ 191.393990] RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007dbc4ff1c574
[ 191.394594] RDX: 0000000000000005 RSI: 00005a6eeadb0ce0 RDI: 0000000000000001
[ 191.395215] RBP: 00007ffd95a23ae0 R08: 00007dbc50003b20 R09: 0000000000000000
[ 191.395805] R10: 0000000000000001 R11: 0000000000000202 R12: 0000000000000005
[ 191.396404] R13: 00005a6eeadb0ce0 R14: 00007dbc500045c0 R15: 00007dbc50001ee0
[ 191.396987] </TASK>
To fix this, we explicitly set such mana debugfs variables to NULL after
debugfs_remove() is called.
Fixes: 6607c17c6c5e ("net: mana: Enable debugfs files for MANA device")
Cc: stable@vger.kernel.org
Signed-off-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Link: https://patch.msgid.link/1741688260-28922-1-git-send-email-shradhagupta@linux.microsoft.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Tariq Toukan says:
====================
mlx5 misc fixes 2025-03-10
This patchset provides misc bug fixes from the team to the mlx5 core and
Eth drivers.
====================
Link: https://patch.msgid.link/1741644104-97767-1-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
mlx5_eswitch_get_vepa returns -EPERM if the device lacks
eswitch_manager capability, blocking mlx5e_bridge_getlink from
retrieving VEPA mode. Since mlx5e_bridge_getlink implements
ndo_bridge_getlink, returning -EPERM causes bridge link show to fail
instead of skipping devices without this capability.
To avoid this, return -EOPNOTSUPP from mlx5e_bridge_getlink when
mlx5_eswitch_get_vepa fails, ensuring the command continues processing
other devices while ignoring those without the necessary capability.
Fixes: 4b89251de024 ("net/mlx5: Support ndo bridge_setlink and getlink")
Signed-off-by: Carolina Jubran <cjubran@nvidia.com>
Reviewed-by: Jianbo Liu <jianbol@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/1741644104-97767-7-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
When removing LAG device from bridge, NETDEV_CHANGEUPPER event is
triggered. Driver finds the lower devices (PFs) to flush all the
offloaded entries. And mlx5_lag_is_shared_fdb is checked, it returns
false if one of PF is unloaded. In such case,
mlx5_esw_bridge_lag_rep_get() and its caller return NULL, instead of
the alive PF, and the flush is skipped.
Besides, the bridge fdb entry's lastuse is updated in mlx5 bridge
event handler. But this SWITCHDEV_FDB_ADD_TO_BRIDGE event can be
ignored in this case because the upper interface for bond is deleted,
and the entry will never be aged because lastuse is never updated.
To make things worse, as the entry is alive, mlx5 bridge workqueue
keeps sending that event, which is then handled by kernel bridge
notifier. It causes the following crash when accessing the passed bond
netdev which is already destroyed.
To fix this issue, remove such checks. LAG state is already checked in
commit 15f8f168952f ("net/mlx5: Bridge, verify LAG state when adding
bond to bridge"), driver still need to skip offload if LAG becomes
invalid state after initialization.
Oops: stack segment: 0000 [#1] SMP
CPU: 3 UID: 0 PID: 23695 Comm: kworker/u40:3 Tainted: G OE 6.11.0_mlnx #1
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: mlx5_bridge_wq mlx5_esw_bridge_update_work [mlx5_core]
RIP: 0010:br_switchdev_event+0x2c/0x110 [bridge]
Code: 44 00 00 48 8b 02 48 f7 00 00 02 00 00 74 69 41 54 55 53 48 83 ec 08 48 8b a8 08 01 00 00 48 85 ed 74 4a 48 83 fe 02 48 89 d3 <4c> 8b 65 00 74 23 76 49 48 83 fe 05 74 7e 48 83 fe 06 75 2f 0f b7
RSP: 0018:ffffc900092cfda0 EFLAGS: 00010297
RAX: ffff888123bfe000 RBX: ffffc900092cfe08 RCX: 00000000ffffffff
RDX: ffffc900092cfe08 RSI: 0000000000000001 RDI: ffffffffa0c585f0
RBP: 6669746f6e690a30 R08: 0000000000000000 R09: ffff888123ae92c8
R10: 0000000000000000 R11: fefefefefefefeff R12: ffff888123ae9c60
R13: 0000000000000001 R14: ffffc900092cfe08 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88852c980000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f15914c8734 CR3: 0000000002830005 CR4: 0000000000770ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __die_body+0x1a/0x60
? die+0x38/0x60
? do_trap+0x10b/0x120
? do_error_trap+0x64/0xa0
? exc_stack_segment+0x33/0x50
? asm_exc_stack_segment+0x22/0x30
? br_switchdev_event+0x2c/0x110 [bridge]
? sched_balance_newidle.isra.149+0x248/0x390
notifier_call_chain+0x4b/0xa0
atomic_notifier_call_chain+0x16/0x20
mlx5_esw_bridge_update+0xec/0x170 [mlx5_core]
mlx5_esw_bridge_update_work+0x19/0x40 [mlx5_core]
process_scheduled_works+0x81/0x390
worker_thread+0x106/0x250
? bh_worker+0x110/0x110
kthread+0xb7/0xe0
? kthread_park+0x80/0x80
ret_from_fork+0x2d/0x50
? kthread_park+0x80/0x80
ret_from_fork_asm+0x11/0x20
</TASK>
Fixes: ff9b7521468b ("net/mlx5: Bridge, support LAG")
Signed-off-by: Jianbo Liu <jianbol@nvidia.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/1741644104-97767-6-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Currently, MultiPort E-Switch is requesting to create a LAG with shared
FDB without checking the LAG is supporting shared FDB.
Add the check.
Fixes: a32327a3a02c ("net/mlx5: Lag, Control MultiPort E-Switch single FDB mode")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/1741644104-97767-5-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
mlx5_irq_pool_get() is a getter for completion IRQ pool only.
However, after the cited commit, mlx5_irq_pool_get() is called during
ctrl IRQ release flow to retrieve the pool, resulting in the use of an
incorrect IRQ pool.
Hence, use the newly introduced mlx5_irq_get_pool() getter to retrieve
the correct IRQ pool based on the IRQ itself. While at it, rename
mlx5_irq_pool_get() to mlx5_irq_table_get_comp_irq_pool() which
accurately reflects its purpose and improves code readability.
Fixes: 0477d5168bbb ("net/mlx5: Expose SFs IRQs")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Maher Sanalla <msanalla@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Link: https://patch.msgid.link/1741644104-97767-4-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
The bwc layer was clamping the matcher priority from 32 bits to 16 bits.
This didn't show up until a matcher was resized, since the initial
native matcher was created using the correct 32 bit value.
The fix also reorders fields to avoid some padding.
Fixes: 2111bb970c78 ("net/mlx5: HWS, added backward-compatible API handling")
Signed-off-by: Vlad Dogaru <vdogaru@nvidia.com>
Reviewed-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1741644104-97767-3-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
Some actions in ConnectX-8 (STEv3) have different structure,
and they are handled separately in ste_ctx_v3.
This separate handling was missing two actions: INSERT_HDR
and REMOVE_HDR, which broke SWS for Linux Bridge.
This patch resolves the issue by introducing dedicated
callbacks for the insert and remove header functions,
with version-specific implementations for each STE variant.
Fixes: 4d617b57574f ("net/mlx5: DR, add support for ConnectX-8 steering")
Signed-off-by: Yevgeny Kliteynik <kliteyn@nvidia.com>
Reviewed-by: Itamar Gozlan <igozlan@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://patch.msgid.link/1741644104-97767-2-git-send-email-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
|
|
The exact timer ID allocation mode is used by CRIU to restore timers with a
given ID. Add a test case for it.
It's skipped on older kernels when the prctl() fails.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/8734fl2tkx.ffs@tglx
|
|
Checkpoint/Restore in Userspace (CRIU) requires to reconstruct posix timers
with the same timer ID on restore. It uses sys_timer_create() and relies on
the monotonic increasing timer ID provided by this syscall. It creates and
deletes timers until the desired ID is reached. This is can loop for a long
time, when the checkpointed process had a very sparse timer ID range.
It has been debated to implement a new syscall to allow the creation of
timers with a given timer ID, but that's tideous due to the 32/64bit compat
issues of sigevent_t and of dubious value.
The restore mechanism of CRIU creates the timers in a state where all
threads of the restored process are held on a barrier and cannot issue
syscalls. That means the restorer task has exclusive control.
This allows to address this issue with a prctl() so that the restorer
thread can do:
if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_ON))
goto linear_mode;
create_timers_with_explicit_ids();
prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_OFF);
This is backwards compatible because the prctl() fails on older kernels and
CRIU can fall back to the linear timer ID mechanism. CRIU versions which do
not know about the prctl() just work as before.
Implement the prctl() and modify timer_create() so that it copies the
requested timer ID from userspace by utilizing the existing timer_t
pointer, which is used to copy out the allocated timer ID on success.
If the prctl() is disabled, which it is by default, timer_create() works as
before and does not try to read from the userspace pointer.
There is no problem when a broken or rogue user space application enables
the prctl(). If the user space pointer does not contain a valid ID, then
timer_create() fails. If the data is not initialized, but constains a
random valid ID, timer_create() will create that random timer ID or fail if
the ID is already given out.
As CRIU must use the raw syscall to avoid manipulating the internal state
of the restored process, this has no library dependencies and can be
adopted by CRIU right away.
Recreating two timers with IDs 1000000 and 2000000 takes 1.5 seconds with
the create/delete method. With the prctl() it takes 3 microseconds.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Tested-by: Cyrill Gorcunov <gorcunov@gmail.com>
Link: https://lore.kernel.org/all/87jz8vz0en.ffs@tglx
|
|
The readout of /proc/$PID/timers holds sighand::siglock with interrupts
disabled. That is required to protect against concurrent modifications of
the task::signal::posix_timers list because the list is not RCU safe.
With the conversion of the timer storage to a RCU protected hlist, this is
not longer required.
The only requirement is to protect the returned entry against a concurrent
free, which is trivial as the timers are RCU protected.
Removing the trylock of sighand::siglock is benign because the life time of
task_struct::signal is bound to the life time of the task_struct itself.
There are two scenarios where this matters:
1) The process is life and not about to be checkpointed
2) The process is stopped via ptrace for checkpointing
#1 is a racy snapshot of the armed timers and nothing can rely on it. It's
not more than debug information and it has been that way before because
sighand lock is dropped when the buffer is full and the restart of
the iteration might find a completely different set of timers.
The task and therefore task::signal cannot be freed as timers_start()
acquired a reference count via get_pid_task().
#2 the process is stopped for checkpointing so nothing can delete or create
timers at this point. Neither can the process exit during the traversal.
If CRIU fails to observe an exit in progress prior to the dissimination
of the timers, then there are more severe problems to solve in the CRIU
mechanics as they can't rely on posix timers being enabled in the first
place.
Therefore replace the lock acquisition with rcu_read_lock() and switch the
timer storage traversal over to seq_hlist_*_rcu().
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250308155624.465175807@linutronix.de
|
|
Preparatory change to remove the sighand locking from the /proc/$PID/timers
iterator.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250308155624.403223080@linutronix.de
|
|
struct k_itimer has the hlist_node, which is used for lookup in the hash
bucket, and the timer lock in the same cache line.
That's obviously bad, if one CPU fiddles with a timer and the other is
walking the hash bucket on which that timer is queued.
Avoid this by restructuring struct k_itimer, so that the read mostly (only
modified during setup and teardown) fields are in the first cache line and
the lock and the rest of the fields which get written to are in cacheline
2-N.
Reduces cacheline contention in a test case of 64 processes creating and
accessing 20000 timers each by almost 30% according to perf.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250308155624.341108067@linutronix.de
|
|
The hash distribution of hash_32() is suboptimal. jhash32() provides a way
better distribution, which evens out the length of the hash bucket lists,
which in turn avoids large outliers in list walk times.
Due to the sparse ID space (thanks CRIU) there is no guarantee that the
timers will be fully evenly distributed over the hash buckets, but the
behaviour is way better than with hash_32() even for randomly sparse ID
spaces.
For a pathological test case with 64 processes creating and accessing
20000 timers each, this results in a runtime reduction of ~10% and a
significantly reduced runtime variation.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250308155624.279080328@linutronix.de
|
|
Eric and Ben reported a significant performance bottleneck on the global
hash, which is used to store posix timers for lookup.
Eric tried to do a lockless validation of a new timer ID before trying to
insert the timer, but that does not solve the problem.
For the non-contended case this is a pointless exercise and for the
contended case this extra lookup just creates enough interleaving that all
tasks can make progress.
There are actually two real solutions to the problem:
1) Provide a per process (signal struct) xarray storage
2) Implement a smarter hash like the one in the futex code
#1 works perfectly fine for most cases, but the fact that CRIU enforced a
linear increasing timer ID to restore timers makes this problematic.
It's easy enough to create a sparse timer ID space, which amounts very
fast to a large junk of memory consumed for the xarray. 2048 timers with
a ID offset of 512 consume more than one megabyte of memory for the
xarray storage.
#2 The main advantage of the futex hash is that it uses per hash bucket
locks instead of a global hash lock. Aside of that it is scaled
according to the number of CPUs at boot time.
Experiments with artifical benchmarks have shown that a scaled hash with
per bucket locks comes pretty close to the xarray performance and in some
scenarios it performes better.
Test 1:
A single process creates 20000 timers and afterwards invokes
timer_getoverrun(2) on each of them:
mainline Eric newhash xarray
create 23 ms 23 ms 9 ms 8 ms
getoverrun 14 ms 14 ms 5 ms 4 ms
Test 2:
A single process creates 50000 timers and afterwards invokes
timer_getoverrun(2) on each of them:
mainline Eric newhash xarray
create 98 ms 219 ms 20 ms 18 ms
getoverrun 62 ms 62 ms 10 ms 9 ms
Test 3:
A single process creates 100000 timers and afterwards invokes
timer_getoverrun(2) on each of them:
mainline Eric newhash xarray
create 313 ms 750 ms 48 ms 33 ms
getoverrun 261 ms 260 ms 20 ms 14 ms
Erics changes create quite some overhead in the create() path due to the
double list walk, as the main issue according to perf is the list walk
itself. With 100k timers each hash bucket contains ~200 timers, which in
the worst case need to be all inspected. The same problem applies for
getoverrun() where the lookup has to walk through the hash buckets to find
the timer it is looking for.
The scaled hash obviously reduces hash collisions and lock contention
significantly. This becomes more prominent with concurrency.
Test 4:
A process creates 63 threads and all threads wait on a barrier before
each instance creates 20000 timers and afterwards invokes
timer_getoverrun(2) on each of them. The threads are pinned on
seperate CPUs to achive maximum concurrency. The numbers are the
average times per thread:
mainline Eric newhash xarray
create 180239 ms 38599 ms 579 ms 813 ms
getoverrun 2645 ms 2642 ms 32 ms 7 ms
Test 5:
A process forks 63 times and all forks wait on a barrier before each
instance creates 20000 timers and afterwards invokes
timer_getoverrun(2) on each of them. The processes are pinned on
seperate CPUs to achive maximum concurrency. The numbers are the
average times per process:
mainline eric newhash xarray
create 157253 ms 40008 ms 83 ms 60 ms
getoverrun 2611 ms 2614 ms 40 ms 4 ms
So clearly the reduction of lock contention with Eric's changes makes a
significant difference for the create() loop, but it does not mitigate the
problem of long list walks, which is clearly visible on the getoverrun()
side because that is purely dominated by the lookup itself. Once the timer
is found, the syscall just reads from the timer structure with no other
locks or code paths involved and returns.
The reason for the difference between the thread and the fork case for the
new hash and the xarray is that both suffer from contention on
sighand::siglock and the xarray suffers additionally from contention on the
xarray lock on insertion.
The only case where the reworked hash slighly outperforms the xarray is a
tight loop which creates and deletes timers.
Test 4:
A process creates 63 threads and all threads wait on a barrier before
each instance runs a loop which creates and deletes a timer 100000
times in a row. The threads are pinned on seperate CPUs to achive
maximum concurrency. The numbers are the average times per thread:
mainline Eric newhash xarray
loop 5917 ms 5897 ms 5473 ms 7846 ms
Test 5:
A process forks 63 times and all forks wait on a barrier before each
each instance runs a loop which creates and deletes a timer 100000
times in a row. The processes are pinned on seperate CPUs to achive
maximum concurrency. The numbers are the average times per process:
mainline Eric newhash xarray
loop 5137 ms 7828 ms 891 ms 872 ms
In both test there is not much contention on the hash, but the ucount
accounting for the signal and in the thread case the sighand::siglock
contention (plus the xarray locking) contribute dominantly to the overhead.
As the memory consumption of the xarray in the sparse ID case is
significant, the scaled hash with per bucket locks seems to be the better
overall option. While the xarray has faster lookup times for a large number
of timers, the actual syscall usage, which requires the lookup is not an
extreme hotpath. Most applications utilize signal delivery and all syscalls
except timer_getoverrun(2) are all but cheap.
So implement a scaled hash with per bucket locks, which offers the best
tradeoff between performance and memory consumption.
Reported-by: Eric Dumazet <edumazet@google.com>
Reported-by: Benjamin Segall <bsegall@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250308155624.216091571@linutronix.de
|
|
The global hash_lock protecting the posix timer hash table can be heavily
contended especially when there is an extensive linear search for a timer
ID.
Timer IDs are handed out by monotonically increasing next_posix_timer_id
and then validating that there is no timer with the same ID in the hash
table. Both operations happen with the global hash lock held.
To reduce the hash lock contention the hash will be reworked to a scaled
hash with per bucket locks, which requires to handle the ID counter
lockless.
Prepare for this by making next_posix_timer_id an atomic_t, which can be
used lockless with atomic_inc_return().
[ tglx: Adopted from Eric's series, massaged change log and simplified it ]
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250219125522.2535263-2-edumazet@google.com
Link: https://lore.kernel.org/all/20250308155624.151545978@linutronix.de
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The lookup and locking of posix timers requires the same repeating pattern
at all usage sites:
tmr = lock_timer(tiner_id);
if (!tmr)
return -EINVAL;
....
unlock_timer(tmr);
Solve this with a guard implementation, which works in most places out of
the box except for those, which need to unlock the timer inside the guard
scope.
Though the only places where this matters are timer_delete() and
timer_settime(). In both cases the timer pointer needs to be preserved
across the end of the scope, which is solved by storing the pointer in a
variable outside of the scope.
timer_settime() also has to protect the timer with RCU before unlocking,
which obviously can't use guard(rcu) before leaving the guard scope as that
guard is cleaned up before the unlock. Solve this by providing the RCU
protection open coded.
[ tglx: Made it work and added change log ]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250224162103.GD11590@noisy.programming.kicks-ass.net
Link: https://lore.kernel.org/all/20250308155624.087465658@linutronix.de
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