The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From 01626a18230246efdcea322aa8f067e60ffe5ccd Mon Sep 17 00:00:00 2001
From: Barry Song <v-songbaohua(a)oppo.com>
Date: Fri, 27 Sep 2024 09:19:36 +1200
Subject: [PATCH] mm: avoid unconditional one-tick sleep when swapcache_prepare
fails
Commit 13ddaf26be32 ("mm/swap: fix race when skipping swapcache")
introduced an unconditional one-tick sleep when `swapcache_prepare()`
fails, which has led to reports of UI stuttering on latency-sensitive
Android devices. To address this, we can use a waitqueue to wake up tasks
that fail `swapcache_prepare()` sooner, instead of always sleeping for a
full tick. While tasks may occasionally be woken by an unrelated
`do_swap_page()`, this method is preferable to two scenarios: rapid
re-entry into page faults, which can cause livelocks, and multiple
millisecond sleeps, which visibly degrade user experience.
Oven's testing shows that a single waitqueue resolves the UI stuttering
issue. If a 'thundering herd' problem becomes apparent later, a waitqueue
hash similar to `folio_wait_table[PAGE_WAIT_TABLE_SIZE]` for page bit
locks can be introduced.
[v-songbaohua(a)oppo.com: wake_up only when swapcache_wq waitqueue is active]
Link: https://lkml.kernel.org/r/20241008130807.40833-1-21cnbao@gmail.com
Link: https://lkml.kernel.org/r/20240926211936.75373-1-21cnbao@gmail.com
Fixes: 13ddaf26be32 ("mm/swap: fix race when skipping swapcache")
Signed-off-by: Barry Song <v-songbaohua(a)oppo.com>
Reported-by: Oven Liyang <liyangouwen1(a)oppo.com>
Tested-by: Oven Liyang <liyangouwen1(a)oppo.com>
Cc: Kairui Song <kasong(a)tencent.com>
Cc: "Huang, Ying" <ying.huang(a)intel.com>
Cc: Yu Zhao <yuzhao(a)google.com>
Cc: David Hildenbrand <david(a)redhat.com>
Cc: Chris Li <chrisl(a)kernel.org>
Cc: Hugh Dickins <hughd(a)google.com>
Cc: Johannes Weiner <hannes(a)cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy(a)infradead.org>
Cc: Michal Hocko <mhocko(a)suse.com>
Cc: Minchan Kim <minchan(a)kernel.org>
Cc: Yosry Ahmed <yosryahmed(a)google.com>
Cc: SeongJae Park <sj(a)kernel.org>
Cc: Kalesh Singh <kaleshsingh(a)google.com>
Cc: Suren Baghdasaryan <surenb(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/memory.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c
index 3ccee51adfbbd..bdf77a3ec47bc 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4187,6 +4187,8 @@ static struct folio *alloc_swap_folio(struct vm_fault *vmf)
}
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+static DECLARE_WAIT_QUEUE_HEAD(swapcache_wq);
+
/*
* We enter with non-exclusive mmap_lock (to exclude vma changes,
* but allow concurrent faults), and pte mapped but not yet locked.
@@ -4199,6 +4201,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct folio *swapcache, *folio = NULL;
+ DECLARE_WAITQUEUE(wait, current);
struct page *page;
struct swap_info_struct *si = NULL;
rmap_t rmap_flags = RMAP_NONE;
@@ -4297,7 +4300,9 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
* Relax a bit to prevent rapid
* repeated page faults.
*/
+ add_wait_queue(&swapcache_wq, &wait);
schedule_timeout_uninterruptible(1);
+ remove_wait_queue(&swapcache_wq, &wait);
goto out_page;
}
need_clear_cache = true;
@@ -4604,8 +4609,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
pte_unmap_unlock(vmf->pte, vmf->ptl);
out:
/* Clear the swap cache pin for direct swapin after PTL unlock */
- if (need_clear_cache)
+ if (need_clear_cache) {
swapcache_clear(si, entry, nr_pages);
+ if (waitqueue_active(&swapcache_wq))
+ wake_up(&swapcache_wq);
+ }
if (si)
put_swap_device(si);
return ret;
@@ -4620,8 +4628,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf)
folio_unlock(swapcache);
folio_put(swapcache);
}
- if (need_clear_cache)
+ if (need_clear_cache) {
swapcache_clear(si, entry, nr_pages);
+ if (waitqueue_active(&swapcache_wq))
+ wake_up(&swapcache_wq);
+ }
if (si)
put_swap_device(si);
return ret;
--
2.43.0
The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From 6575b268157f37929948a8d1f3bafb3d7c055bc1 Mon Sep 17 00:00:00 2001
From: Dan Williams <dan.j.williams(a)intel.com>
Date: Fri, 25 Oct 2024 12:32:55 -0700
Subject: [PATCH] cxl/port: Fix CXL port initialization order when the
subsystem is built-in
When the CXL subsystem is built-in the module init order is determined
by Makefile order. That order violates expectations. The expectation is
that cxl_acpi and cxl_mem can race to attach. If cxl_acpi wins the race,
cxl_mem will find the enabled CXL root ports it needs. If cxl_acpi loses
the race it will retrigger cxl_mem to attach via cxl_bus_rescan(). That
flow only works if cxl_acpi can assume ports are enabled immediately
upon cxl_acpi_probe() return. That in turn can only happen in the
CONFIG_CXL_ACPI=y case if the cxl_port driver is registered before
cxl_acpi_probe() runs.
Fix up the order to prevent initialization failures. Ensure that
cxl_port is built-in when cxl_acpi is also built-in, arrange for
Makefile order to resolve the subsys_initcall() order of cxl_port and
cxl_acpi, and arrange for Makefile order to resolve the
device_initcall() (module_init()) order of the remaining objects.
As for what contributed to this not being found earlier, the CXL
regression environment, cxl_test, builds all CXL functionality as a
module to allow to symbol mocking and other dynamic reload tests. As a
result there is no regression coverage for the built-in case.
Reported-by: Gregory Price <gourry(a)gourry.net>
Closes: http://lore.kernel.org/20241004212504.1246-1-gourry@gourry.net
Tested-by: Gregory Price <gourry(a)gourry.net>
Fixes: 8dd2bc0f8e02 ("cxl/mem: Add the cxl_mem driver")
Cc: stable(a)vger.kernel.org
Cc: Davidlohr Bueso <dave(a)stgolabs.net>
Cc: Jonathan Cameron <jonathan.cameron(a)huawei.com>
Cc: Dave Jiang <dave.jiang(a)intel.com>
Cc: Alison Schofield <alison.schofield(a)intel.com>
Cc: Vishal Verma <vishal.l.verma(a)intel.com>
Cc: Ira Weiny <ira.weiny(a)intel.com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron(a)huawei.com>
Reviewed-by: Ira Weiny <ira.weiny(a)intel.com>
Tested-by: Alejandro Lucero <alucerop(a)amd.com>
Reviewed-by: Alejandro Lucero <alucerop(a)amd.com>
Signed-off-by: Dan Williams <dan.j.williams(a)intel.com>
Link: https://patch.msgid.link/172988474904.476062.7961350937442459266.stgit@dwil…
Signed-off-by: Ira Weiny <ira.weiny(a)intel.com>
---
drivers/cxl/Kconfig | 1 +
drivers/cxl/Makefile | 20 ++++++++++++++------
drivers/cxl/port.c | 17 ++++++++++++++++-
3 files changed, 31 insertions(+), 7 deletions(-)
diff --git a/drivers/cxl/Kconfig b/drivers/cxl/Kconfig
index 29c192f20082c..876469e23f7a7 100644
--- a/drivers/cxl/Kconfig
+++ b/drivers/cxl/Kconfig
@@ -60,6 +60,7 @@ config CXL_ACPI
default CXL_BUS
select ACPI_TABLE_LIB
select ACPI_HMAT
+ select CXL_PORT
help
Enable support for host managed device memory (HDM) resources
published by a platform's ACPI CXL memory layout description. See
diff --git a/drivers/cxl/Makefile b/drivers/cxl/Makefile
index db321f48ba52e..2caa90fa4bf25 100644
--- a/drivers/cxl/Makefile
+++ b/drivers/cxl/Makefile
@@ -1,13 +1,21 @@
# SPDX-License-Identifier: GPL-2.0
+
+# Order is important here for the built-in case:
+# - 'core' first for fundamental init
+# - 'port' before platform root drivers like 'acpi' so that CXL-root ports
+# are immediately enabled
+# - 'mem' and 'pmem' before endpoint drivers so that memdevs are
+# immediately enabled
+# - 'pci' last, also mirrors the hardware enumeration hierarchy
obj-y += core/
-obj-$(CONFIG_CXL_PCI) += cxl_pci.o
-obj-$(CONFIG_CXL_MEM) += cxl_mem.o
+obj-$(CONFIG_CXL_PORT) += cxl_port.o
obj-$(CONFIG_CXL_ACPI) += cxl_acpi.o
obj-$(CONFIG_CXL_PMEM) += cxl_pmem.o
-obj-$(CONFIG_CXL_PORT) += cxl_port.o
+obj-$(CONFIG_CXL_MEM) += cxl_mem.o
+obj-$(CONFIG_CXL_PCI) += cxl_pci.o
-cxl_mem-y := mem.o
-cxl_pci-y := pci.o
+cxl_port-y := port.o
cxl_acpi-y := acpi.o
cxl_pmem-y := pmem.o security.o
-cxl_port-y := port.o
+cxl_mem-y := mem.o
+cxl_pci-y := pci.o
diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c
index 861dde65768fe..9dc394295e1fc 100644
--- a/drivers/cxl/port.c
+++ b/drivers/cxl/port.c
@@ -208,7 +208,22 @@ static struct cxl_driver cxl_port_driver = {
},
};
-module_cxl_driver(cxl_port_driver);
+static int __init cxl_port_init(void)
+{
+ return cxl_driver_register(&cxl_port_driver);
+}
+/*
+ * Be ready to immediately enable ports emitted by the platform CXL root
+ * (e.g. cxl_acpi) when CONFIG_CXL_PORT=y.
+ */
+subsys_initcall(cxl_port_init);
+
+static void __exit cxl_port_exit(void)
+{
+ cxl_driver_unregister(&cxl_port_driver);
+}
+module_exit(cxl_port_exit);
+
MODULE_DESCRIPTION("CXL: Port enumeration and services");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS(CXL);
--
2.43.0
The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From 7245012f0f496162dd95d888ed2ceb5a35170f1a Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg(a)intel.com>
Date: Wed, 23 Oct 2024 09:17:44 +0200
Subject: [PATCH] wifi: iwlwifi: mvm: fix 6 GHz scan construction
If more than 255 colocated APs exist for the set of all
APs found during 2.4/5 GHz scanning, then the 6 GHz scan
construction will loop forever since the loop variable
has type u8, which can never reach the number found when
that's bigger than 255, and is stored in a u32 variable.
Also move it into the loops to have a smaller scope.
Using a u32 there is fine, we limit the number of APs in
the scan list and each has a limit on the number of RNR
entries due to the frame size. With a limit of 1000 scan
results, a frame size upper bound of 4096 (really it's
more like ~2300) and a TBTT entry size of at least 11,
we get an upper bound for the number of ~372k, well in
the bounds of a u32.
Cc: stable(a)vger.kernel.org
Fixes: eae94cf82d74 ("iwlwifi: mvm: add support for 6GHz")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219375
Link: https://patch.msgid.link/20241023091744.f4baed5c08a1.I8b417148bbc8c5d11c101…
Signed-off-by: Johannes Berg <johannes.berg(a)intel.com>
---
drivers/net/wireless/intel/iwlwifi/mvm/scan.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/scan.c b/drivers/net/wireless/intel/iwlwifi/mvm/scan.c
index 3ce9150213a74..ddcbd80a49fb2 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/scan.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/scan.c
@@ -1774,7 +1774,7 @@ iwl_mvm_umac_scan_cfg_channels_v7_6g(struct iwl_mvm *mvm,
&cp->channel_config[ch_cnt];
u32 s_ssid_bitmap = 0, bssid_bitmap = 0, flags = 0;
- u8 j, k, n_s_ssids = 0, n_bssids = 0;
+ u8 k, n_s_ssids = 0, n_bssids = 0;
u8 max_s_ssids, max_bssids;
bool force_passive = false, found = false, allow_passive = true,
unsolicited_probe_on_chan = false, psc_no_listen = false;
@@ -1799,7 +1799,7 @@ iwl_mvm_umac_scan_cfg_channels_v7_6g(struct iwl_mvm *mvm,
cfg->v5.iter_count = 1;
cfg->v5.iter_interval = 0;
- for (j = 0; j < params->n_6ghz_params; j++) {
+ for (u32 j = 0; j < params->n_6ghz_params; j++) {
s8 tmp_psd_20;
if (!(scan_6ghz_params[j].channel_idx == i))
@@ -1873,7 +1873,7 @@ iwl_mvm_umac_scan_cfg_channels_v7_6g(struct iwl_mvm *mvm,
* SSID.
* TODO: improve this logic
*/
- for (j = 0; j < params->n_6ghz_params; j++) {
+ for (u32 j = 0; j < params->n_6ghz_params; j++) {
if (!(scan_6ghz_params[j].channel_idx == i))
continue;
--
2.43.0
The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From a0f0625390858321525c2a8d04e174a546bd19b3 Mon Sep 17 00:00:00 2001
From: Filipe Manana <fdmanana(a)suse.com>
Date: Mon, 28 Oct 2024 16:23:00 +0000
Subject: [PATCH] btrfs: fix extent map merging not happening for adjacent
extents
If we have 3 or more adjacent extents in a file, that is, consecutive file
extent items pointing to adjacent extents, within a contiguous file range
and compatible flags, we end up not merging all the extents into a single
extent map.
For example:
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt/sdc
$ xfs_io -f -d -c "pwrite -b 64K 0 64K" \
-c "pwrite -b 64K 64K 64K" \
-c "pwrite -b 64K 128K 64K" \
-c "pwrite -b 64K 192K 64K" \
/mnt/sdc/foo
After all the ordered extents complete we unpin the extent maps and try
to merge them, but instead of getting a single extent map we get two
because:
1) When the first ordered extent completes (file range [0, 64K)) we
unpin its extent map and attempt to merge it with the extent map for
the range [64K, 128K), but we can't because that extent map is still
pinned;
2) When the second ordered extent completes (file range [64K, 128K)), we
unpin its extent map and merge it with the previous extent map, for
file range [0, 64K), but we can't merge with the next extent map, for
the file range [128K, 192K), because this one is still pinned.
The merged extent map for the file range [0, 128K) gets the flag
EXTENT_MAP_MERGED set;
3) When the third ordered extent completes (file range [128K, 192K)), we
unpin its extent map and attempt to merge it with the previous extent
map, for file range [0, 128K), but we can't because that extent map
has the flag EXTENT_MAP_MERGED set (mergeable_maps() returns false
due to different flags) while the extent map for the range [128K, 192K)
doesn't have that flag set.
We also can't merge it with the next extent map, for file range
[192K, 256K), because that one is still pinned.
At this moment we have 3 extent maps:
One for file range [0, 128K), with the flag EXTENT_MAP_MERGED set.
One for file range [128K, 192K).
One for file range [192K, 256K) which is still pinned;
4) When the fourth and final extent completes (file range [192K, 256K)),
we unpin its extent map and attempt to merge it with the previous
extent map, for file range [128K, 192K), which succeeds since none
of these extent maps have the EXTENT_MAP_MERGED flag set.
So we end up with 2 extent maps:
One for file range [0, 128K), with the flag EXTENT_MAP_MERGED set.
One for file range [128K, 256K), with the flag EXTENT_MAP_MERGED set.
Since after merging extent maps we don't attempt to merge again, that
is, merge the resulting extent map with the one that is now preceding
it (and the one following it), we end up with those two extent maps,
when we could have had a single extent map to represent the whole file.
Fix this by making mergeable_maps() ignore the EXTENT_MAP_MERGED flag.
While this doesn't present any functional issue, it prevents the merging
of extent maps which allows to save memory, and can make defrag not
merging extents too (that will be addressed in the next patch).
Fixes: 199257a78bb0 ("btrfs: defrag: don't use merged extent map for their generation check")
CC: stable(a)vger.kernel.org # 6.1+
Reviewed-by: Qu Wenruo <wqu(a)suse.com>
Signed-off-by: Filipe Manana <fdmanana(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
---
fs/btrfs/extent_map.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 668c617444a50..1d93e1202c339 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -230,7 +230,12 @@ static bool mergeable_maps(const struct extent_map *prev, const struct extent_ma
if (extent_map_end(prev) != next->start)
return false;
- if (prev->flags != next->flags)
+ /*
+ * The merged flag is not an on-disk flag, it just indicates we had the
+ * extent maps of 2 (or more) adjacent extents merged, so factor it out.
+ */
+ if ((prev->flags & ~EXTENT_FLAG_MERGED) !=
+ (next->flags & ~EXTENT_FLAG_MERGED))
return false;
if (next->disk_bytenr < EXTENT_MAP_LAST_BYTE - 1)
--
2.43.0
The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From aec8e6bf839101784f3ef037dcdb9432c3f32343 Mon Sep 17 00:00:00 2001
From: Zhihao Cheng <chengzhihao1(a)huawei.com>
Date: Mon, 21 Oct 2024 22:02:15 +0800
Subject: [PATCH] btrfs: fix use-after-free of block device file in
__btrfs_free_extra_devids()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Mounting btrfs from two images (which have the same one fsid and two
different dev_uuids) in certain executing order may trigger an UAF for
variable 'device->bdev_file' in __btrfs_free_extra_devids(). And
following are the details:
1. Attach image_1 to loop0, attach image_2 to loop1, and scan btrfs
devices by ioctl(BTRFS_IOC_SCAN_DEV):
/ btrfs_device_1 → loop0
fs_device
\ btrfs_device_2 → loop1
2. mount /dev/loop0 /mnt
btrfs_open_devices
btrfs_device_1->bdev_file = btrfs_get_bdev_and_sb(loop0)
btrfs_device_2->bdev_file = btrfs_get_bdev_and_sb(loop1)
btrfs_fill_super
open_ctree
fail: btrfs_close_devices // -ENOMEM
btrfs_close_bdev(btrfs_device_1)
fput(btrfs_device_1->bdev_file)
// btrfs_device_1->bdev_file is freed
btrfs_close_bdev(btrfs_device_2)
fput(btrfs_device_2->bdev_file)
3. mount /dev/loop1 /mnt
btrfs_open_devices
btrfs_get_bdev_and_sb(&bdev_file)
// EIO, btrfs_device_1->bdev_file is not assigned,
// which points to a freed memory area
btrfs_device_2->bdev_file = btrfs_get_bdev_and_sb(loop1)
btrfs_fill_super
open_ctree
btrfs_free_extra_devids
if (btrfs_device_1->bdev_file)
fput(btrfs_device_1->bdev_file) // UAF !
Fix it by setting 'device->bdev_file' as 'NULL' after closing the
btrfs_device in btrfs_close_one_device().
Fixes: 142388194191 ("btrfs: do not background blkdev_put()")
CC: stable(a)vger.kernel.org # 4.19+
Link: https://bugzilla.kernel.org/show_bug.cgi?id=219408
Signed-off-by: Zhihao Cheng <chengzhihao1(a)huawei.com>
Reviewed-by: David Sterba <dsterba(a)suse.com>
Signed-off-by: David Sterba <dsterba(a)suse.com>
---
fs/btrfs/volumes.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 8f340ad1d9384..eb51b609190fb 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1105,6 +1105,7 @@ static void btrfs_close_one_device(struct btrfs_device *device)
if (device->bdev) {
fs_devices->open_devices--;
device->bdev = NULL;
+ device->bdev_file = NULL;
}
clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
btrfs_destroy_dev_zone_info(device);
--
2.43.0
The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From d949d1d14fa281ace388b1de978e8f2cd52875cf Mon Sep 17 00:00:00 2001
From: Jeongjun Park <aha310510(a)gmail.com>
Date: Mon, 9 Sep 2024 21:35:58 +0900
Subject: [PATCH] mm: shmem: fix data-race in shmem_getattr()
I got the following KCSAN report during syzbot testing:
==================================================================
BUG: KCSAN: data-race in generic_fillattr / inode_set_ctime_current
write to 0xffff888102eb3260 of 4 bytes by task 6565 on cpu 1:
inode_set_ctime_to_ts include/linux/fs.h:1638 [inline]
inode_set_ctime_current+0x169/0x1d0 fs/inode.c:2626
shmem_mknod+0x117/0x180 mm/shmem.c:3443
shmem_create+0x34/0x40 mm/shmem.c:3497
lookup_open fs/namei.c:3578 [inline]
open_last_lookups fs/namei.c:3647 [inline]
path_openat+0xdbc/0x1f00 fs/namei.c:3883
do_filp_open+0xf7/0x200 fs/namei.c:3913
do_sys_openat2+0xab/0x120 fs/open.c:1416
do_sys_open fs/open.c:1431 [inline]
__do_sys_openat fs/open.c:1447 [inline]
__se_sys_openat fs/open.c:1442 [inline]
__x64_sys_openat+0xf3/0x120 fs/open.c:1442
x64_sys_call+0x1025/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:258
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
read to 0xffff888102eb3260 of 4 bytes by task 3498 on cpu 0:
inode_get_ctime_nsec include/linux/fs.h:1623 [inline]
inode_get_ctime include/linux/fs.h:1629 [inline]
generic_fillattr+0x1dd/0x2f0 fs/stat.c:62
shmem_getattr+0x17b/0x200 mm/shmem.c:1157
vfs_getattr_nosec fs/stat.c:166 [inline]
vfs_getattr+0x19b/0x1e0 fs/stat.c:207
vfs_statx_path fs/stat.c:251 [inline]
vfs_statx+0x134/0x2f0 fs/stat.c:315
vfs_fstatat+0xec/0x110 fs/stat.c:341
__do_sys_newfstatat fs/stat.c:505 [inline]
__se_sys_newfstatat+0x58/0x260 fs/stat.c:499
__x64_sys_newfstatat+0x55/0x70 fs/stat.c:499
x64_sys_call+0x141f/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:263
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x54/0x120 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x76/0x7e
value changed: 0x2755ae53 -> 0x27ee44d3
Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3498 Comm: udevd Not tainted 6.11.0-rc6-syzkaller-00326-gd1f2d51b711a-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
==================================================================
When calling generic_fillattr(), if you don't hold read lock, data-race
will occur in inode member variables, which can cause unexpected
behavior.
Since there is no special protection when shmem_getattr() calls
generic_fillattr(), data-race occurs by functions such as shmem_unlink()
or shmem_mknod(). This can cause unexpected results, so commenting it out
is not enough.
Therefore, when calling generic_fillattr() from shmem_getattr(), it is
appropriate to protect the inode using inode_lock_shared() and
inode_unlock_shared() to prevent data-race.
Link: https://lkml.kernel.org/r/20240909123558.70229-1-aha310510@gmail.com
Fixes: 44a30220bc0a ("shmem: recalculate file inode when fstat")
Signed-off-by: Jeongjun Park <aha310510(a)gmail.com>
Reported-by: syzbot <syzkaller(a)googlegroup.com>
Cc: Hugh Dickins <hughd(a)google.com>
Cc: Yu Zhao <yuzhao(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
mm/shmem.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/mm/shmem.c b/mm/shmem.c
index c5adb987b23cf..4ba1d00fabdaa 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -1166,7 +1166,9 @@ static int shmem_getattr(struct mnt_idmap *idmap,
stat->attributes_mask |= (STATX_ATTR_APPEND |
STATX_ATTR_IMMUTABLE |
STATX_ATTR_NODUMP);
+ inode_lock_shared(inode);
generic_fillattr(idmap, request_mask, inode, stat);
+ inode_unlock_shared(inode);
if (shmem_huge_global_enabled(inode, 0, 0, false, NULL, 0))
stat->blksize = HPAGE_PMD_SIZE;
--
2.43.0
The patch below does not apply to the v6.1-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From ddd6d8e975b171ea3f63a011a75820883ff0d479 Mon Sep 17 00:00:00 2001
From: Yu Zhao <yuzhao(a)google.com>
Date: Sat, 19 Oct 2024 01:29:38 +0000
Subject: [PATCH] mm: multi-gen LRU: remove MM_LEAF_OLD and MM_NONLEAF_TOTAL
stats
Patch series "mm: multi-gen LRU: Have secondary MMUs participate in
MM_WALK".
Today, the MM_WALK capability causes MGLRU to clear the young bit from
PMDs and PTEs during the page table walk before eviction, but MGLRU does
not call the clear_young() MMU notifier in this case. By not calling this
notifier, the MM walk takes less time/CPU, but it causes pages that are
accessed mostly through KVM / secondary MMUs to appear younger than they
should be.
We do call the clear_young() notifier today, but only when attempting to
evict the page, so we end up clearing young/accessed information less
frequently for secondary MMUs than for mm PTEs, and therefore they appear
younger and are less likely to be evicted. Therefore, memory that is
*not* being accessed mostly by KVM will be evicted *more* frequently,
worsening performance.
ChromeOS observed a tab-open latency regression when enabling MGLRU with a
setup that involved running a VM:
Tab-open latency histogram (ms)
Version p50 mean p95 p99 max
base 1315 1198 2347 3454 10319
mglru 2559 1311 7399 12060 43758
fix 1119 926 2470 4211 6947
This series replaces the final non-selftest patchs from this series[1],
which introduced a similar change (and a new MMU notifier) with KVM
optimizations. I'll send a separate series (to Sean and Paolo) for the
KVM optimizations.
This series also makes proactive reclaim with MGLRU possible for KVM
memory. I have verified that this functions correctly with the selftest
from [1], but given that that test is a KVM selftest, I'll send it with
the rest of the KVM optimizations later. Andrew, let me know if you'd
like to take the test now anyway.
[1]: https://lore.kernel.org/linux-mm/20240926013506.860253-18-jthoughton@google…
This patch (of 2):
The removed stats, MM_LEAF_OLD and MM_NONLEAF_TOTAL, are not very helpful
and become more complicated to properly compute when adding
test/clear_young() notifiers in MGLRU's mm walk.
Link: https://lkml.kernel.org/r/20241019012940.3656292-1-jthoughton@google.com
Link: https://lkml.kernel.org/r/20241019012940.3656292-2-jthoughton@google.com
Fixes: bd74fdaea146 ("mm: multi-gen LRU: support page table walks")
Signed-off-by: Yu Zhao <yuzhao(a)google.com>
Signed-off-by: James Houghton <jthoughton(a)google.com>
Cc: Axel Rasmussen <axelrasmussen(a)google.com>
Cc: David Matlack <dmatlack(a)google.com>
Cc: David Rientjes <rientjes(a)google.com>
Cc: David Stevens <stevensd(a)google.com>
Cc: Oliver Upton <oliver.upton(a)linux.dev>
Cc: Paolo Bonzini <pbonzini(a)redhat.com>
Cc: Sean Christopherson <seanjc(a)google.com>
Cc: Wei Xu <weixugc(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
include/linux/mmzone.h | 2 --
mm/vmscan.c | 14 +++++---------
2 files changed, 5 insertions(+), 11 deletions(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 17506e4a28355..9342e5692dab6 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -458,9 +458,7 @@ struct lru_gen_folio {
enum {
MM_LEAF_TOTAL, /* total leaf entries */
- MM_LEAF_OLD, /* old leaf entries */
MM_LEAF_YOUNG, /* young leaf entries */
- MM_NONLEAF_TOTAL, /* total non-leaf entries */
MM_NONLEAF_FOUND, /* non-leaf entries found in Bloom filters */
MM_NONLEAF_ADDED, /* non-leaf entries added to Bloom filters */
NR_MM_STATS
diff --git a/mm/vmscan.c b/mm/vmscan.c
index eb4e8440c5071..4f1d33e4b3601 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -3399,7 +3399,6 @@ static bool walk_pte_range(pmd_t *pmd, unsigned long start, unsigned long end,
continue;
if (!pte_young(ptent)) {
- walk->mm_stats[MM_LEAF_OLD]++;
continue;
}
@@ -3552,7 +3551,6 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end,
walk->mm_stats[MM_LEAF_TOTAL]++;
if (!pmd_young(val)) {
- walk->mm_stats[MM_LEAF_OLD]++;
continue;
}
@@ -3564,8 +3562,6 @@ static void walk_pmd_range(pud_t *pud, unsigned long start, unsigned long end,
continue;
}
- walk->mm_stats[MM_NONLEAF_TOTAL]++;
-
if (!walk->force_scan && should_clear_pmd_young()) {
if (!pmd_young(val))
continue;
@@ -5254,11 +5250,11 @@ static void lru_gen_seq_show_full(struct seq_file *m, struct lruvec *lruvec,
for (tier = 0; tier < MAX_NR_TIERS; tier++) {
seq_printf(m, " %10d", tier);
for (type = 0; type < ANON_AND_FILE; type++) {
- const char *s = " ";
+ const char *s = "xxx";
unsigned long n[3] = {};
if (seq == max_seq) {
- s = "RT ";
+ s = "RTx";
n[0] = READ_ONCE(lrugen->avg_refaulted[type][tier]);
n[1] = READ_ONCE(lrugen->avg_total[type][tier]);
} else if (seq == min_seq[type] || NR_HIST_GENS > 1) {
@@ -5280,14 +5276,14 @@ static void lru_gen_seq_show_full(struct seq_file *m, struct lruvec *lruvec,
seq_puts(m, " ");
for (i = 0; i < NR_MM_STATS; i++) {
- const char *s = " ";
+ const char *s = "xxxx";
unsigned long n = 0;
if (seq == max_seq && NR_HIST_GENS == 1) {
- s = "LOYNFA";
+ s = "TYFA";
n = READ_ONCE(mm_state->stats[hist][i]);
} else if (seq != max_seq && NR_HIST_GENS > 1) {
- s = "loynfa";
+ s = "tyfa";
n = READ_ONCE(mm_state->stats[hist][i]);
}
--
2.43.0
The patch below does not apply to the v6.6-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>.
Thanks,
Sasha
------------------ original commit in Linus's tree ------------------
From 1b6063a57754eae5705753c01e78dc268b989038 Mon Sep 17 00:00:00 2001
From: Ovidiu Bunea <Ovidiu.Bunea(a)amd.com>
Date: Fri, 11 Oct 2024 11:12:19 -0400
Subject: [PATCH] Revert "drm/amd/display: update DML2 policy
EnhancedPrefetchScheduleAccelerationFinal DCN35"
This reverts
commit 9dad21f910fc ("drm/amd/display: update DML2 policy EnhancedPrefetchScheduleAccelerationFinal DCN35")
[why & how]
The offending commit exposes a hang with lid close/open behavior.
Both issues seem to be related to ODM 2:1 mode switching, so there
is another issue generic to that sequence that needs to be
investigated.
Cc: Mario Limonciello <mario.limonciello(a)amd.com>
Cc: Alex Deucher <alexander.deucher(a)amd.com>
Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas(a)amd.com>
Signed-off-by: Ovidiu Bunea <Ovidiu.Bunea(a)amd.com>
Signed-off-by: Tom Chung <chiahsuan.chung(a)amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler(a)amd.com>
Signed-off-by: Alex Deucher <alexander.deucher(a)amd.com>
(cherry picked from commit 68bf95317ebf2cfa7105251e4279e951daceefb7)
Cc: stable(a)vger.kernel.org
---
drivers/gpu/drm/amd/display/dc/dml2/dml2_policy.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_policy.c b/drivers/gpu/drm/amd/display/dc/dml2/dml2_policy.c
index 11c904ae29586..c4c52173ef224 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_policy.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_policy.c
@@ -303,6 +303,7 @@ void build_unoptimized_policy_settings(enum dml_project_id project, struct dml_m
if (project == dml_project_dcn35 ||
project == dml_project_dcn351) {
policy->DCCProgrammingAssumesScanDirectionUnknownFinal = false;
+ policy->EnhancedPrefetchScheduleAccelerationFinal = 0;
policy->AllowForPStateChangeOrStutterInVBlankFinal = dml_prefetch_support_uclk_fclk_and_stutter_if_possible; /*new*/
policy->UseOnlyMaxPrefetchModes = 1;
}
--
2.43.0