Every time I run test srp/002 the following deadlock is triggered:
task:multipathd
Call Trace:
<TASK>
__schedule+0x8c1/0x1bf0
schedule+0xdd/0x270
schedule_preempt_disabled+0x1c/0x30
__mutex_lock+0xb89/0x1650
mutex_lock_nested+0x1f/0x30
dm_table_set_restrictions+0x823/0xdf0
__bind+0x166/0x590
dm_swap_table+0x2a7/0x490
do_resume+0x1b1/0x610
dev_suspend+0x55/0x1a0
ctl_ioctl+0x3a5/0x7e0
dm_ctl_ioctl+0x12/0x20
__x64_sys_ioctl+0x127/0x1a0
x64_sys_call+0xe2b/0x17d0
do_syscall_64+0x96/0x3a0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
task:(udev-worker)
Call Trace:
<TASK>
__schedule+0x8c1/0x1bf0
schedule+0xdd/0x270
blk_mq_freeze_queue_wait+0xf2/0x140
blk_mq_freeze_queue_nomemsave+0x23/0x30
queue_ra_store+0x14e/0x290
queue_attr_store+0x23e/0x2c0
sysfs_kf_write+0xde/0x140
kernfs_fop_write_iter+0x3b2/0x630
vfs_write+0x4fd/0x1390
ksys_write+0xfd/0x230
__x64_sys_write+0x76/0xc0
x64_sys_call+0x276/0x17d0
do_syscall_64+0x96/0x3a0
entry_SYSCALL_64_after_hwframe+0x4b/0x53
</TASK>
This deadlock happens because blk_mq_freeze_queue_nomemsave() waits for
pending requests to finish. The pending requests do never complete because
the dm-multipath queue_if_no_path option is enabled and the only path in
the dm-multipath configuration is being removed.
Fix this deadlock by removing the queue freezing/unfreezing code from
queue_ra_store().
Freezing the request queue from inside a block layer sysfs store callback
function is essential when modifying parameters that affect how bios or
requests are processed, e.g. parameters that affect bio_split_to_limit().
Freezing the request queue when modifying parameters that do not affect bio
nor request processing is not necessary.
Cc: Nilay Shroff <nilay(a)linux.ibm.com>
Cc: stable(a)vger.kernel.org
Fixes: b07a889e8335 ("block: move q->sysfs_lock and queue-freeze under show/store method")
Signed-off-by: Bart Van Assche <bvanassche(a)acm.org>
---
Changes compared to v1: made the patch description more detailed.
block/blk-sysfs.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index b2b9b89d6967..1f63b184c6e9 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -105,7 +105,6 @@ queue_ra_store(struct gendisk *disk, const char *page, size_t count)
{
unsigned long ra_kb;
ssize_t ret;
- unsigned int memflags;
struct request_queue *q = disk->queue;
ret = queue_var_store(&ra_kb, page, count);
@@ -116,10 +115,8 @@ queue_ra_store(struct gendisk *disk, const char *page, size_t count)
* calculated from the queue limits by queue_limits_commit_update.
*/
mutex_lock(&q->limits_lock);
- memflags = blk_mq_freeze_queue(q);
disk->bdi->ra_pages = ra_kb >> (PAGE_SHIFT - 10);
mutex_unlock(&q->limits_lock);
- blk_mq_unfreeze_queue(q, memflags);
return ret;
}
The patch below does not apply to the 6.15-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.15.y
git checkout FETCH_HEAD
git cherry-pick -x 7f8073cfb04a97842fe891ca50dad60afd1e3121
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062928-revival-saint-3ba2@gregkh' --subject-prefix 'PATCH 6.15.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 7f8073cfb04a97842fe891ca50dad60afd1e3121 Mon Sep 17 00:00:00 2001
From: Heiko Carstens <hca(a)linux.ibm.com>
Date: Fri, 13 Jun 2025 17:53:04 +0200
Subject: [PATCH] s390/ptrace: Fix pointer dereferencing in
regs_get_kernel_stack_nth()
The recent change which added READ_ONCE_NOCHECK() to read the nth entry
from the kernel stack incorrectly dropped dereferencing of the stack
pointer in order to read the requested entry.
In result the address of the entry is returned instead of its content.
Dereference the pointer again to fix this.
Reported-by: Will Deacon <will(a)kernel.org>
Closes: https://lore.kernel.org/r/20250612163331.GA13384@willie-the-truck
Fixes: d93a855c31b7 ("s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()")
Cc: stable(a)vger.kernel.org
Reviewed-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
Signed-off-by: Heiko Carstens <hca(a)linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev(a)linux.ibm.com>
diff --git a/arch/s390/include/asm/ptrace.h b/arch/s390/include/asm/ptrace.h
index 62c0ab4a4b9d..0905fa99a31e 100644
--- a/arch/s390/include/asm/ptrace.h
+++ b/arch/s390/include/asm/ptrace.h
@@ -265,7 +265,7 @@ static __always_inline unsigned long regs_get_kernel_stack_nth(struct pt_regs *r
addr = kernel_stack_pointer(regs) + n * sizeof(long);
if (!regs_within_kernel_stack(regs, addr))
return 0;
- return READ_ONCE_NOCHECK(addr);
+ return READ_ONCE_NOCHECK(*(unsigned long *)addr);
}
/**
The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x b07f349d1864abe29436f45e3047da2bdd476462
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025063006-expose-blandness-ffd5@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From b07f349d1864abe29436f45e3047da2bdd476462 Mon Sep 17 00:00:00 2001
From: Khairul Anuar Romli <khairul.anuar.romli(a)altera.com>
Date: Mon, 16 Jun 2025 09:13:53 +0800
Subject: [PATCH] spi: spi-cadence-quadspi: Fix pm runtime unbalance
Having PM put sync in remove function is causing PM underflow during
remove operation. This is caused by the function, runtime_pm_get_sync,
not being called anywhere during the op. Ensure that calls to
pm_runtime_enable()/pm_runtime_disable() and
pm_runtime_get_sync()/pm_runtime_put_sync() match.
echo 108d2000.spi > /sys/bus/platform/drivers/cadence-qspi/unbind
[ 49.644256] Deleting MTD partitions on "108d2000.spi.0":
[ 49.649575] Deleting u-boot MTD partition
[ 49.684087] Deleting root MTD partition
[ 49.724188] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
Continuous bind/unbind will result in an "Unbalanced pm_runtime_enable" error.
Subsequent unbind attempts will return a "No such device" error, while bind
attempts will return a "Resource temporarily unavailable" error.
[ 47.592434] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[ 49.592233] cadence-qspi 108d2000.spi: detected FIFO depth (1024) different from config (128)
[ 53.232309] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[ 55.828550] cadence-qspi 108d2000.spi: detected FIFO depth (1024) different from config (128)
[ 57.940627] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[ 59.912490] cadence-qspi 108d2000.spi: detected FIFO depth (1024) different from config (128)
[ 61.876243] cadence-qspi 108d2000.spi: Runtime PM usage count underflow!
[ 61.883000] platform 108d2000.spi: Unbalanced pm_runtime_enable!
[ 532.012270] cadence-qspi 108d2000.spi: probe with driver cadence-qspi failed1
Also, change clk_disable_unprepare() to clk_disable() since continuous
bind and unbind operations will trigger a warning indicating that the clock is
already unprepared.
Fixes: 4892b374c9b7 ("mtd: spi-nor: cadence-quadspi: Add runtime PM support")
cc: stable(a)vger.kernel.org # 6.6+
Signed-off-by: Khairul Anuar Romli <khairul.anuar.romli(a)altera.com>
Reviewed-by: Matthew Gerlach <matthew.gerlach(a)altera.com>
Link: https://patch.msgid.link/4e7a4b8aba300e629b45a04f90bddf665fbdb335.174960187…
Signed-off-by: Mark Brown <broonie(a)kernel.org>
diff --git a/drivers/spi/spi-cadence-quadspi.c b/drivers/spi/spi-cadence-quadspi.c
index fe0f122f07b0..aa1932ba17cb 100644
--- a/drivers/spi/spi-cadence-quadspi.c
+++ b/drivers/spi/spi-cadence-quadspi.c
@@ -1958,10 +1958,10 @@ static int cqspi_probe(struct platform_device *pdev)
goto probe_setup_failed;
}
- ret = devm_pm_runtime_enable(dev);
- if (ret) {
- if (cqspi->rx_chan)
- dma_release_channel(cqspi->rx_chan);
+ pm_runtime_enable(dev);
+
+ if (cqspi->rx_chan) {
+ dma_release_channel(cqspi->rx_chan);
goto probe_setup_failed;
}
@@ -1981,6 +1981,7 @@ static int cqspi_probe(struct platform_device *pdev)
return 0;
probe_setup_failed:
cqspi_controller_enable(cqspi, 0);
+ pm_runtime_disable(dev);
probe_reset_failed:
if (cqspi->is_jh7110)
cqspi_jh7110_disable_clk(pdev, cqspi);
@@ -1999,7 +2000,8 @@ static void cqspi_remove(struct platform_device *pdev)
if (cqspi->rx_chan)
dma_release_channel(cqspi->rx_chan);
- clk_disable_unprepare(cqspi->clk);
+ if (pm_runtime_get_sync(&pdev->dev) >= 0)
+ clk_disable(cqspi->clk);
if (cqspi->is_jh7110)
cqspi_jh7110_disable_clk(pdev, cqspi);
The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y
git checkout FETCH_HEAD
git cherry-pick -x 0cf4b1687a187ba9247c71721d8b064634eda1f7
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025062053-gills-deliverer-bafc@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 0cf4b1687a187ba9247c71721d8b064634eda1f7 Mon Sep 17 00:00:00 2001
From: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Date: Fri, 6 Jun 2025 13:50:32 +0100
Subject: [PATCH] mm/vma: reset VMA iterator on commit_merge() OOM failure
While an OOM failure in commit_merge() isn't really feasible due to the
allocation which might fail (a maple tree pre-allocation) being 'too small
to fail', we do need to handle this case correctly regardless.
In vma_merge_existing_range(), we can theoretically encounter failures
which result in an OOM error in two ways - firstly dup_anon_vma() might
fail with an OOM error, and secondly commit_merge() failing, ultimately,
to pre-allocate a maple tree node.
The abort logic for dup_anon_vma() resets the VMA iterator to the initial
range, ensuring that any logic looping on this iterator will correctly
proceed to the next VMA.
However the commit_merge() abort logic does not do the same thing. This
resulted in a syzbot report occurring because mlockall() iterates through
VMAs, is tolerant of errors, but ended up with an incorrect previous VMA
being specified due to incorrect iterator state.
While making this change, it became apparent we are duplicating logic -
the logic introduced in commit 41e6ddcaa0f1 ("mm/vma: add give_up_on_oom
option on modify/merge, use in uffd release") duplicates the
vmg->give_up_on_oom check in both abort branches.
Additionally, we observe that we can perform the anon_dup check safely on
dup_anon_vma() failure, as this will not be modified should this call
fail.
Finally, we need to reset the iterator in both cases, so now we can simply
use the exact same code to abort for both.
We remove the VM_WARN_ON(err != -ENOMEM) as it would be silly for this to
be otherwise and it allows us to implement the abort check more neatly.
Link: https://lkml.kernel.org/r/20250606125032.164249-1-lorenzo.stoakes@oracle.com
Fixes: 47b16d0462a4 ("mm: abort vma_modify() on merge out of memory failure")
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com>
Reported-by: syzbot+d16409ea9ecc16ed261a(a)syzkaller.appspotmail.com
Closes: https://lore.kernel.org/linux-mm/6842cc67.a00a0220.29ac89.003b.GAE@google.c…
Reviewed-by: Pedro Falcato <pfalcato(a)suse.de>
Reviewed-by: Vlastimil Babka <vbabka(a)suse.cz>
Reviewed-by: Liam R. Howlett <Liam.Howlett(a)oracle.com>
Cc: Jann Horn <jannh(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
diff --git a/mm/vma.c b/mm/vma.c
index 726b2a31ce59..0fb9b2c7b734 100644
--- a/mm/vma.c
+++ b/mm/vma.c
@@ -967,26 +967,9 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
err = dup_anon_vma(next, middle, &anon_dup);
}
- if (err)
+ if (err || commit_merge(vmg))
goto abort;
- err = commit_merge(vmg);
- if (err) {
- VM_WARN_ON(err != -ENOMEM);
-
- if (anon_dup)
- unlink_anon_vmas(anon_dup);
-
- /*
- * We've cleaned up any cloned anon_vma's, no VMAs have been
- * modified, no harm no foul if the user requests that we not
- * report this and just give up, leaving the VMAs unmerged.
- */
- if (!vmg->give_up_on_oom)
- vmg->state = VMA_MERGE_ERROR_NOMEM;
- return NULL;
- }
-
khugepaged_enter_vma(vmg->target, vmg->flags);
vmg->state = VMA_MERGE_SUCCESS;
return vmg->target;
@@ -995,6 +978,9 @@ static __must_check struct vm_area_struct *vma_merge_existing_range(
vma_iter_set(vmg->vmi, start);
vma_iter_load(vmg->vmi);
+ if (anon_dup)
+ unlink_anon_vmas(anon_dup);
+
/*
* This means we have failed to clone anon_vma's correctly, but no
* actual changes to VMAs have occurred, so no harm no foul - if the