[BUG]
When running btrfs with block size (4K) smaller than page size (64K,
aarch64), there is a very high chance to crash the kernel at
generic/750, with the following messages:
(before the call traces, there are 3 extra debug messages added)
BTRFS warning (device dm-3): read-write for sector size 4096 with page size 65536 is experimental
BTRFS info (device dm-3): checking UUID tree
hrtimer: interrupt took 5451385 ns
BTRFS error (device dm-3): cow_file_range failed, root=4957 inode=257 start=1605632 len=69632: -28
BTRFS error (device dm-3): run_delalloc_nocow failed, root=4957 inode=257 start=1605632 len=69632: -28
BTRFS error (device dm-3): failed to run delalloc range, root=4957 ino=257 folio=1572864 submit_bitmap=8-15 start=1605632 len=69632: -28
------------[ cut here ]------------
WARNING: CPU: 2 PID: 3020984 at ordered-data.c:360 can_finish_ordered_extent+0x370/0x3b8 [btrfs]
CPU: 2 UID: 0 PID: 3020984 Comm: kworker/u24:1 Tainted: G OE 6.13.0-rc1-custom+ #89
Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
Workqueue: events_unbound btrfs_async_reclaim_data_space [btrfs]
pc : can_finish_ordered_extent+0x370/0x3b8 [btrfs]
lr : can_finish_ordered_extent+0x1ec/0x3b8 [btrfs]
Call trace:
can_finish_ordered_extent+0x370/0x3b8 [btrfs] (P)
can_finish_ordered_extent+0x1ec/0x3b8 [btrfs] (L)
btrfs_mark_ordered_io_finished+0x130/0x2b8 [btrfs]
extent_writepage+0x10c/0x3b8 [btrfs]
extent_write_cache_pages+0x21c/0x4e8 [btrfs]
btrfs_writepages+0x94/0x160 [btrfs]
do_writepages+0x74/0x190
filemap_fdatawrite_wbc+0x74/0xa0
start_delalloc_inodes+0x17c/0x3b0 [btrfs]
btrfs_start_delalloc_roots+0x17c/0x288 [btrfs]
shrink_delalloc+0x11c/0x280 [btrfs]
flush_space+0x288/0x328 [btrfs]
btrfs_async_reclaim_data_space+0x180/0x228 [btrfs]
process_one_work+0x228/0x680
worker_thread+0x1bc/0x360
kthread+0x100/0x118
ret_from_fork+0x10/0x20
---[ end trace 0000000000000000 ]---
BTRFS critical (device dm-3): bad ordered extent accounting, root=4957 ino=257 OE offset=1605632 OE len=16384 to_dec=16384 left=0
BTRFS critical (device dm-3): bad ordered extent accounting, root=4957 ino=257 OE offset=1622016 OE len=12288 to_dec=12288 left=0
Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008
BTRFS critical (device dm-3): bad ordered extent accounting, root=4957 ino=257 OE offset=1634304 OE len=8192 to_dec=4096 left=0
CPU: 1 UID: 0 PID: 3286940 Comm: kworker/u24:3 Tainted: G W OE 6.13.0-rc1-custom+ #89
Hardware name: QEMU KVM Virtual Machine, BIOS unknown 2/2/2022
Workqueue: btrfs_work_helper [btrfs] (btrfs-endio-write)
pstate: 404000c5 (nZcv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : process_one_work+0x110/0x680
lr : worker_thread+0x1bc/0x360
Call trace:
process_one_work+0x110/0x680 (P)
worker_thread+0x1bc/0x360 (L)
worker_thread+0x1bc/0x360
kthread+0x100/0x118
ret_from_fork+0x10/0x20
Code: f84086a1 f9000fe1 53041c21 b9003361 (f9400661)
---[ end trace 0000000000000000 ]---
Kernel panic - not syncing: Oops: Fatal exception
SMP: stopping secondary CPUs
SMP: failed to stop secondary CPUs 2-3
Dumping ftrace buffer:
(ftrace buffer empty)
Kernel Offset: 0x275bb9540000 from 0xffff800080000000
PHYS_OFFSET: 0xffff8fbba0000000
CPU features: 0x100,00000070,00801250,8201720b
[CAUSE]
The above warning is triggered immediately after the delalloc range
failure, this happens in the following sequence:
- Range [1568K, 1636K) is dirty
1536K 1568K 1600K 1636K 1664K
| |/////////|////////| |
Where 1536K, 1600K and 1664K are page boundaries (64K page size)
- Enter extent_writepage() for page 1536K
- Enter run_delalloc_nocow() with locked page 1536K and range
[1568K, 1636K)
This is due to the inode has preallocated extents.
- Enter cow_file_range() with locked page 1536K and range
[1568K, 1636K)
- btrfs_reserve_extent() only reserved two extents
The main loop of cow_file_range() only reserved two data extents,
Now we have:
1536K 1568K 1600K 1636K 1664K
| |<-->|<--->|/|///////| |
1584K 1596K
Range [1568K, 1596K) has ordered extent reserved.
- btrfs_reserve_extent() failed inside cow_file_range() for file offset
1596K
This is already a bug in our space reservation code, but for now let's
focus on the error handling path.
Now cow_file_range() returned -ENOSPC.
- btrfs_run_delalloc_range() do error cleanup <<< ROOT CAUSE
Call btrfs_cleanup_ordered_extents() with locked folio 1536K and range
[1568K, 1636K)
Function btrfs_cleanup_ordered_extents() normally needs to skip the
ranges inside the folio, as it will normally be cleaned up by
extent_writepage().
Such split error handling is already problematic in the first place.
What's worse is the folio range skipping itself, which is not taking
subpage cases into consideration at all, it will only skip the range
if the page start >= the range start.
In our case, the page start < the range start, since for subpage cases
we can have delalloc ranges inside the folio but not covering the
folio.
So it doesn't skip the page range at all.
This means all the ordered extents, both [1568K, 1584K) and
[1584K, 1596K) will be marked as IOERR.
And those two ordered extents have no more pending ios, it is marked
finished, and *QUEUED* to be deleted from the io tree.
- extent_writepage() do error cleanup
Call btrfs_mark_ordered_io_finished() for the range [1536K, 1600K).
Although ranges [1568K, 1584K) and [1584K, 1596K) are finished, the
deletion from io tree is async, it may or may not happen at this
timing.
If the ranges are not yet removed, we will do double cleaning on those
ranges, triggers the above ordered extent warnings.
In theory there are other bugs, like the cleanup in extent_writepage()
can cause double accounting on ranges that are submitted async
(compression for example).
But that's much harder to trigger because normally we do not mix regular
and compression delalloc ranges.
[FIX]
The folio range split is already buggy and not subpage compatible, it's
introduced a long time ago where subpage support is not even considered.
So instead of splitting the ordered extents cleanup into the folio range
and out of folio range, do all the cleanup inside writepage_delalloc().
- Pass @NULL as locked_folio for btrfs_cleanup_ordered_extents() in
btrfs_run_delalloc_range()
- Skip the btrfs_cleanup_ordered_extents() if writepage_delalloc()
failed
So all ordered extents are only cleaned up by
btrfs_run_delalloc_range().
- Handle the ranges that already have ordered extents allocated
If part of the folio already has ordered extent allocated, and
btrfs_run_delalloc_range() failed, we also need to cleanup that range.
Now we have a concentrated error handling for ordered extents during
btrfs_run_delalloc_range().
Cc: stable(a)vger.kernel.org # 5.15+
Fixes: d1051d6ebf8e ("btrfs: Fix error handling in btrfs_cleanup_ordered_extents")
Reviewed-by: Boris Burkov <boris(a)bur.io>
Signed-off-by: Qu Wenruo <wqu(a)suse.com>
---
fs/btrfs/extent_io.c | 57 ++++++++++++++++++++++++++++++++++++--------
fs/btrfs/inode.c | 2 +-
2 files changed, 48 insertions(+), 11 deletions(-)
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index c068a442753c..7aa3d8c2b0c3 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1136,12 +1136,17 @@ static bool find_next_delalloc_bitmap(struct folio *folio,
/*
* helper for extent_writepage(), doing all of the delayed allocation setup.
*
- * This returns 1 if btrfs_run_delalloc_range function did all the work required
- * to write the page (copy into inline extent). In this case the IO has
- * been started and the page is already unlocked.
+ * Return >0 if all the dirty blocks are submitted async (compression) or inlined.
+ * The @folio should no longer be touched (treat it as already unlocked).
*
- * This returns 0 if all went well (page still locked)
- * This returns < 0 if there were errors (page still locked)
+ * Return 0 if there is still dirty block that needs to be submitted through
+ * extent_writepage_io().
+ * bio_ctrl->submit_bitmap will indicate which blocks of the folio should be
+ * submitted, and @folio is still kept locked.
+ *
+ * Return <0 if there is any error hit.
+ * Any allocated ordered extent range covering this folio will be marked
+ * finished (IOERR), and @folio is still kept locked.
*/
static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
struct folio *folio,
@@ -1159,6 +1164,16 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
* last delalloc end.
*/
u64 last_delalloc_end = 0;
+ /*
+ * The range end (exclusive) of the last successfully finished delalloc
+ * range.
+ * Any range covered by ordered extent must either be manually marked
+ * finished (error handling), or has IO submitted (and finish the
+ * ordered extent normally).
+ *
+ * This records the end of ordered extent cleanup if we hit an error.
+ */
+ u64 last_finished_delalloc_end = page_start;
u64 delalloc_start = page_start;
u64 delalloc_end = page_end;
u64 delalloc_to_write = 0;
@@ -1227,11 +1242,19 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
found_len = last_delalloc_end + 1 - found_start;
if (ret >= 0) {
+ /*
+ * Some delalloc range may be created by previous folios.
+ * Thus we still need to clean those range up during error
+ * handling.
+ */
+ last_finished_delalloc_end = found_start;
/* No errors hit so far, run the current delalloc range. */
ret = btrfs_run_delalloc_range(inode, folio,
found_start,
found_start + found_len - 1,
wbc);
+ if (ret >= 0)
+ last_finished_delalloc_end = found_start + found_len;
} else {
/*
* We've hit an error during previous delalloc range,
@@ -1266,8 +1289,22 @@ static noinline_for_stack int writepage_delalloc(struct btrfs_inode *inode,
delalloc_start = found_start + found_len;
}
- if (ret < 0)
+ /*
+ * It's possible we have some ordered extents created before we hit
+ * an error, cleanup non-async successfully created delalloc ranges.
+ */
+ if (unlikely(ret < 0)) {
+ unsigned int bitmap_size = min(
+ (last_finished_delalloc_end - page_start) >>
+ fs_info->sectorsize_bits,
+ fs_info->sectors_per_page);
+
+ for_each_set_bit(bit, &bio_ctrl->submit_bitmap, bitmap_size)
+ btrfs_mark_ordered_io_finished(inode, folio,
+ page_start + (bit << fs_info->sectorsize_bits),
+ fs_info->sectorsize, false);
return ret;
+ }
out:
if (last_delalloc_end)
delalloc_end = last_delalloc_end;
@@ -1501,13 +1538,13 @@ static int extent_writepage(struct folio *folio, struct btrfs_bio_ctrl *bio_ctrl
bio_ctrl->wbc->nr_to_write--;
-done:
- if (ret) {
+ if (ret)
btrfs_mark_ordered_io_finished(inode, folio,
page_start, PAGE_SIZE, !ret);
- mapping_set_error(folio->mapping, ret);
- }
+done:
+ if (ret < 0)
+ mapping_set_error(folio->mapping, ret);
/*
* Only unlock ranges that are submitted. As there can be some async
* submitted ranges inside the folio.
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1546f341f9a4..85e36dbe1e1f 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2301,7 +2301,7 @@ int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct folio *locked_fol
out:
if (ret < 0)
- btrfs_cleanup_ordered_extents(inode, locked_folio, start,
+ btrfs_cleanup_ordered_extents(inode, NULL, start,
end - start + 1);
return ret;
}
--
2.47.1
lockdep detects the following circular locking dependency:
CPU 0 CPU 1
========================== ============================
cdns_uart_isr() printk()
uart_port_lock(port) console_lock()
cdns_uart_console_write()
if (!port->sysrq)
uart_port_lock(port)
uart_handle_break()
port->sysrq = ...
uart_handle_sysrq_char()
printk()
console_lock()
The fixed commit attempts to avoid this situation by only taking the
port lock in cdns_uart_console_write if port->sysrq unset. However, if
(as shown above) cdns_uart_console_write runs before port->sysrq is set,
then it will try to take the port lock anyway. This may result in a
deadlock.
Fix this by splitting sysrq handling into two parts. We use the prepare
helper under the port lock and defer handling until we release the lock.
Fixes: 74ea66d4ca06 ("tty: xuartps: Improve sysrq handling")
Signed-off-by: Sean Anderson <sean.anderson(a)linux.dev>
Cc: <stable(a)vger.kernel.org> # c980248179d: serial: xilinx_uartps: Use port lock wrappers
---
drivers/tty/serial/xilinx_uartps.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index beb151be4d32..92ec51870d1d 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -287,7 +287,7 @@ static void cdns_uart_handle_rx(void *dev_id, unsigned int isrstatus)
continue;
}
- if (uart_handle_sysrq_char(port, data))
+ if (uart_prepare_sysrq_char(port, data))
continue;
if (is_rxbs_support) {
@@ -495,7 +495,7 @@ static irqreturn_t cdns_uart_isr(int irq, void *dev_id)
!(readl(port->membase + CDNS_UART_CR) & CDNS_UART_CR_RX_DIS))
cdns_uart_handle_rx(dev_id, isrstatus);
- uart_port_unlock(port);
+ uart_unlock_and_check_sysrq(port);
return IRQ_HANDLED;
}
@@ -1380,9 +1380,7 @@ static void cdns_uart_console_write(struct console *co, const char *s,
unsigned int imr, ctrl;
int locked = 1;
- if (port->sysrq)
- locked = 0;
- else if (oops_in_progress)
+ if (oops_in_progress)
locked = uart_port_trylock_irqsave(port, &flags);
else
uart_port_lock_irqsave(port, &flags);
--
2.35.1.1320.gc452695387.dirty
Currently, on book3s-hv, the capability KVM_CAP_SPAPR_TCE_VFIO is only
available for KVM Guests running on PowerNV and not for the KVM guests
running on pSeries hypervisors. This prevents a pSeries hypervisor from
leveraging the in-kernel acceleration for H_PUT_TCE_INDIRECT and
H_STUFF_TCE hcalls that results in slow startup times for large memory
guests.
Fix this by enabling the CAP_SPAPR_TCE_VFIO on the pSeries hosts for the
nested PAPR guests.
Fixes: f431a8cde7f1 ("powerpc/iommu: Reimplement the iommu_table_group_ops for pSeries")
Cc: stable(a)vger.kernel.org
Signed-off-by: Amit Machhiwal <amachhiw(a)linux.ibm.com>
---
arch/powerpc/kvm/powerpc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index ce1d91eed231..9c479c7381e4 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -554,7 +554,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
r = 1;
break;
case KVM_CAP_SPAPR_TCE_VFIO:
- r = !!cpu_has_feature(CPU_FTR_HVMODE);
+ r = !!cpu_has_feature(CPU_FTR_HVMODE) || is_kvmppc_hv_enabled(kvm);
break;
case KVM_CAP_PPC_RTAS:
case KVM_CAP_PPC_FIXUP_HCALL:
base-commit: eea6e4b4dfb8859446177c32961c96726d0117be
--
2.47.1
The patch titled
Subject: scripts/gdb: fix aarch64 userspace detection in get_current_task
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
scripts-gdb-fix-aarch64-userspace-detection-in-get_current_task.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Jan Kiszka <jan.kiszka(a)siemens.com>
Subject: scripts/gdb: fix aarch64 userspace detection in get_current_task
Date: Fri, 10 Jan 2025 11:36:33 +0100
At least recent gdb releases (seen with 14.2) return SP_EL0 as signed long
which lets the right-shift always return 0.
Link: https://lkml.kernel.org/r/dcd2fabc-9131-4b48-8419-6444e2d67454@siemens.com
Signed-off-by: Jan Kiszka <jan.kiszka(a)siemens.com>
Cc: Barry Song <baohua(a)kernel.org>
Cc: Kieran Bingham <kbingham(a)kernel.org>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
scripts/gdb/linux/cpus.py | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/scripts/gdb/linux/cpus.py~scripts-gdb-fix-aarch64-userspace-detection-in-get_current_task
+++ a/scripts/gdb/linux/cpus.py
@@ -167,7 +167,7 @@ def get_current_task(cpu):
var_ptr = gdb.parse_and_eval("&pcpu_hot.current_task")
return per_cpu(var_ptr, cpu).dereference()
elif utils.is_target_arch("aarch64"):
- current_task_addr = gdb.parse_and_eval("$SP_EL0")
+ current_task_addr = gdb.parse_and_eval("(unsigned long)$SP_EL0")
if (current_task_addr >> 63) != 0:
current_task = current_task_addr.cast(task_ptr_type)
return current_task.dereference()
_
Patches currently in -mm which might be from jan.kiszka(a)siemens.com are
scripts-gdb-fix-aarch64-userspace-detection-in-get_current_task.patch
The patch titled
Subject: mm/vmscan: fix pgdemote_* accounting with lru_gen_enabled
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-vmscan-fix-pgdemote_-accounting-with-lru_gen_enabled.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Li Zhijian <lizhijian(a)fujitsu.com>
Subject: mm/vmscan: fix pgdemote_* accounting with lru_gen_enabled
Date: Fri, 10 Jan 2025 20:21:33 +0800
Commit f77f0c751478 ("mm,memcg: provide per-cgroup counters for NUMA
balancing operations") moved the accounting of PGDEMOTE_* statistics to
shrink_inactive_list(). However, shrink_inactive_list() is not called
when lrugen_enabled is true, leading to incorrect demotion statistics
despite actual demotion events occurring.
Add the PGDEMOTE_* accounting in evict_folios(), ensuring that demotion
statistics are correctly updated regardless of the lru_gen_enabled state.
This fix is crucial for systems that rely on accurate NUMA balancing
metrics for performance tuning and resource management.
Link: https://lkml.kernel.org/r/20250110122133.423481-2-lizhijian@fujitsu.com
Fixes: f77f0c751478 ("mm,memcg: provide per-cgroup counters for NUMA balancing operations")
Signed-off-by: Li Zhijian <lizhijian(a)fujitsu.com>
Cc: Kaiyang Zhao <kaiyang2(a)cs.cmu.edu>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/vmscan.c | 2 ++
1 file changed, 2 insertions(+)
--- a/mm/vmscan.c~mm-vmscan-fix-pgdemote_-accounting-with-lru_gen_enabled
+++ a/mm/vmscan.c
@@ -4649,6 +4649,8 @@ retry:
__mod_lruvec_state(lruvec, PGDEMOTE_KSWAPD + reclaimer_offset(),
stat.nr_demoted);
+ __mod_lruvec_state(lruvec, PGDEMOTE_KSWAPD + reclaimer_offset(),
+ stat.nr_demoted);
item = PGSTEAL_KSWAPD + reclaimer_offset();
if (!cgroup_reclaim(sc))
__count_vm_events(item, reclaimed);
_
Patches currently in -mm which might be from lizhijian(a)fujitsu.com are
mm-vmscan-accumulate-nr_demoted-for-accurate-demotion-statistics.patch
mm-vmscan-fix-pgdemote_-accounting-with-lru_gen_enabled.patch
selftests-mm-add-a-few-missing-gitignore-files.patch
The patch titled
Subject: mm/vmscan: accumulate nr_demoted for accurate demotion statistics
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
mm-vmscan-accumulate-nr_demoted-for-accurate-demotion-statistics.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Li Zhijian <lizhijian(a)fujitsu.com>
Subject: mm/vmscan: accumulate nr_demoted for accurate demotion statistics
Date: Fri, 10 Jan 2025 20:21:32 +0800
In shrink_folio_list(), demote_folio_list() can be called multiple times,
which can lead to inaccurate demotion statistics if the number of demoted
pages is not accumulated correctly.
Accumulate the nr_demoted count across multiple calls to
demote_folio_list(), ensuring accurate reporting of demotion statistics.
Link: https://lkml.kernel.org/r/20250110122133.423481-1-lizhijian@fujitsu.com
Fixes: f77f0c751478 ("mm,memcg: provide per-cgroup counters for NUMA balancing operations")
Signed-off-by: Li Zhijian <lizhijian(a)fujitsu.com>
Acked-by: Kaiyang Zhao <kaiyang2(a)cs.cmu.edu>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/vmscan.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/mm/vmscan.c~mm-vmscan-accumulate-nr_demoted-for-accurate-demotion-statistics
+++ a/mm/vmscan.c
@@ -1522,7 +1522,7 @@ keep:
/* 'folio_list' is always empty here */
/* Migrate folios selected for demotion */
- stat->nr_demoted = demote_folio_list(&demote_folios, pgdat);
+ stat->nr_demoted += demote_folio_list(&demote_folios, pgdat);
nr_reclaimed += stat->nr_demoted;
/* Folios that could not be demoted are still in @demote_folios */
if (!list_empty(&demote_folios)) {
_
Patches currently in -mm which might be from lizhijian(a)fujitsu.com are
mm-vmscan-accumulate-nr_demoted-for-accurate-demotion-statistics.patch
selftests-mm-add-a-few-missing-gitignore-files.patch
The patch titled
Subject: fs/proc: fix softlockup in __read_vmcore (part 2)
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
fs-proc-fix-softlockup-in-__read_vmcore-part-2.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche…
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next via the mm-everything
branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days
------------------------------------------------------
From: Rik van Riel <riel(a)surriel.com>
Subject: fs/proc: fix softlockup in __read_vmcore (part 2)
Date: Fri, 10 Jan 2025 10:28:21 -0500
Since commit 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore") the
number of softlockups in __read_vmcore at kdump time have gone down, but
they still happen sometimes.
In a memory constrained environment like the kdump image, a softlockup is
not just a harmless message, but it can interfere with things like RCU
freeing memory, causing the crashdump to get stuck.
The second loop in __read_vmcore has a lot more opportunities for natural
sleep points, like scheduling out while waiting for a data write to
happen, but apparently that is not always enough.
Add a cond_resched() to the second loop in __read_vmcore to (hopefully)
get rid of the softlockups.
Link: https://lkml.kernel.org/r/20250110102821.2a37581b@fangorn
Fixes: 5cbcb62dddf5 ("fs/proc: fix softlockup in __read_vmcore")
Signed-off-by: Rik van Riel <riel(a)surriel.com>
Reported-by: Breno Leitao <leitao(a)debian.org>
Cc: Baoquan He <bhe(a)redhat.com>
Cc: Dave Young <dyoung(a)redhat.com>
Cc: Vivek Goyal <vgoyal(a)redhat.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
fs/proc/vmcore.c | 2 ++
1 file changed, 2 insertions(+)
--- a/fs/proc/vmcore.c~fs-proc-fix-softlockup-in-__read_vmcore-part-2
+++ a/fs/proc/vmcore.c
@@ -404,6 +404,8 @@ static ssize_t __read_vmcore(struct iov_
if (!iov_iter_count(iter))
return acc;
}
+
+ cond_resched();
}
return acc;
_
Patches currently in -mm which might be from riel(a)surriel.com are
fs-proc-fix-softlockup-in-__read_vmcore-part-2.patch
mm-remove-unnecessary-calls-to-lru_add_drain.patch
Recent reports have shown how we sometimes call vsock_*_has_data()
when a vsock socket has been de-assigned from a transport (see attached
links), but we shouldn't.
Previous commits should have solved the real problems, but we may have
more in the future, so to avoid null-ptr-deref, we can return 0
(no space, no data available) but with a warning.
This way the code should continue to run in a nearly consistent state
and have a warning that allows us to debug future problems.
Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
Cc: stable(a)vger.kernel.org
Link: https://lore.kernel.org/netdev/Z2K%2FI4nlHdfMRTZC@v4bel-B760M-AORUS-ELITE-A…
Link: https://lore.kernel.org/netdev/5ca20d4c-1017-49c2-9516-f6f75fd331e9@rbox.co/
Link: https://lore.kernel.org/netdev/677f84a8.050a0220.25a300.01b3.GAE@google.com/
Co-developed-by: Hyunwoo Kim <v4bel(a)theori.io>
Signed-off-by: Hyunwoo Kim <v4bel(a)theori.io>
Co-developed-by: Wongi Lee <qwerty(a)theori.io>
Signed-off-by: Wongi Lee <qwerty(a)theori.io>
Signed-off-by: Stefano Garzarella <sgarzare(a)redhat.com>
---
net/vmw_vsock/af_vsock.c | 9 +++++++++
1 file changed, 9 insertions(+)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c
index 74d35a871644..fa9d1b49599b 100644
--- a/net/vmw_vsock/af_vsock.c
+++ b/net/vmw_vsock/af_vsock.c
@@ -879,6 +879,9 @@ EXPORT_SYMBOL_GPL(vsock_create_connected);
s64 vsock_stream_has_data(struct vsock_sock *vsk)
{
+ if (WARN_ON(!vsk->transport))
+ return 0;
+
return vsk->transport->stream_has_data(vsk);
}
EXPORT_SYMBOL_GPL(vsock_stream_has_data);
@@ -887,6 +890,9 @@ s64 vsock_connectible_has_data(struct vsock_sock *vsk)
{
struct sock *sk = sk_vsock(vsk);
+ if (WARN_ON(!vsk->transport))
+ return 0;
+
if (sk->sk_type == SOCK_SEQPACKET)
return vsk->transport->seqpacket_has_data(vsk);
else
@@ -896,6 +902,9 @@ EXPORT_SYMBOL_GPL(vsock_connectible_has_data);
s64 vsock_stream_has_space(struct vsock_sock *vsk)
{
+ if (WARN_ON(!vsk->transport))
+ return 0;
+
return vsk->transport->stream_has_space(vsk);
}
EXPORT_SYMBOL_GPL(vsock_stream_has_space);
--
2.47.1
During virtio_transport_release() we can schedule a delayed work to
perform the closing of the socket before destruction.
The destructor is called either when the socket is really destroyed
(reference counter to zero), or it can also be called when we are
de-assigning the transport.
In the former case, we are sure the delayed work has completed, because
it holds a reference until it completes, so the destructor will
definitely be called after the delayed work is finished.
But in the latter case, the destructor is called by AF_VSOCK core, just
after the release(), so there may still be delayed work scheduled.
Refactor the code, moving the code to delete the close work already in
the do_close() to a new function. Invoke it during destruction to make
sure we don't leave any pending work.
Fixes: c0cfa2d8a788 ("vsock: add multi-transports support")
Cc: stable(a)vger.kernel.org
Reported-by: Hyunwoo Kim <v4bel(a)theori.io>
Closes: https://lore.kernel.org/netdev/Z37Sh+utS+iV3+eb@v4bel-B760M-AORUS-ELITE-AX/
Signed-off-by: Stefano Garzarella <sgarzare(a)redhat.com>
---
net/vmw_vsock/virtio_transport_common.c | 29 ++++++++++++++++++-------
1 file changed, 21 insertions(+), 8 deletions(-)
diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c
index 51a494b69be8..7f7de6d88096 100644
--- a/net/vmw_vsock/virtio_transport_common.c
+++ b/net/vmw_vsock/virtio_transport_common.c
@@ -26,6 +26,9 @@
/* Threshold for detecting small packets to copy */
#define GOOD_COPY_LEN 128
+static void virtio_transport_cancel_close_work(struct vsock_sock *vsk,
+ bool cancel_timeout);
+
static const struct virtio_transport *
virtio_transport_get_ops(struct vsock_sock *vsk)
{
@@ -1109,6 +1112,8 @@ void virtio_transport_destruct(struct vsock_sock *vsk)
{
struct virtio_vsock_sock *vvs = vsk->trans;
+ virtio_transport_cancel_close_work(vsk, true);
+
kfree(vvs);
vsk->trans = NULL;
}
@@ -1204,17 +1209,11 @@ static void virtio_transport_wait_close(struct sock *sk, long timeout)
}
}
-static void virtio_transport_do_close(struct vsock_sock *vsk,
- bool cancel_timeout)
+static void virtio_transport_cancel_close_work(struct vsock_sock *vsk,
+ bool cancel_timeout)
{
struct sock *sk = sk_vsock(vsk);
- sock_set_flag(sk, SOCK_DONE);
- vsk->peer_shutdown = SHUTDOWN_MASK;
- if (vsock_stream_has_data(vsk) <= 0)
- sk->sk_state = TCP_CLOSING;
- sk->sk_state_change(sk);
-
if (vsk->close_work_scheduled &&
(!cancel_timeout || cancel_delayed_work(&vsk->close_work))) {
vsk->close_work_scheduled = false;
@@ -1226,6 +1225,20 @@ static void virtio_transport_do_close(struct vsock_sock *vsk,
}
}
+static void virtio_transport_do_close(struct vsock_sock *vsk,
+ bool cancel_timeout)
+{
+ struct sock *sk = sk_vsock(vsk);
+
+ sock_set_flag(sk, SOCK_DONE);
+ vsk->peer_shutdown = SHUTDOWN_MASK;
+ if (vsock_stream_has_data(vsk) <= 0)
+ sk->sk_state = TCP_CLOSING;
+ sk->sk_state_change(sk);
+
+ virtio_transport_cancel_close_work(vsk, cancel_timeout);
+}
+
static void virtio_transport_close_timeout(struct work_struct *work)
{
struct vsock_sock *vsk =
--
2.47.1