The nr_dentry_negative counter is intended to only account negative
dentries that are present on the superblock LRU. Therefore, the LRU
add, remove and isolate helpers modify the counter based on whether
the dentry is negative, but the shrinker list related helpers do not
modify the counter, and the paths that change a dentry between
positive and negative only do so if DCACHE_LRU_LIST is set.

The problem with this is that a dentry on a shrinker list still has
DCACHE_LRU_LIST set to indicate ->d_lru is in use. The additional
DCACHE_SHRINK_LIST flag denotes whether the dentry is on LRU or a
shrink related list. Therefore if a relevant operation (i.e. unlink)
occurs while a dentry is present on a shrinker list, and the
associated codepath only checks for DCACHE_LRU_LIST, then it is
technically possible to modify the negative dentry count for a
dentry that is off the LRU. Since the shrinker list related helpers
do not modify the negative dentry count (because non-LRU dentries
should not be included in the count) when the dentry is ultimately
removed from the shrinker list, this can cause the negative dentry
count to become permanently inaccurate.

This problem can be reproduced via a heavy file create/unlink vs.
drop_caches workload. On an 80xcpu system, I start 80 tasks each
running a 1k file create/delete loop, and one task spinning on
drop_caches. After 10 minutes or so of runtime, the idle/clean cache
negative dentry count increases from somewhere in the range of 5-10
entries to several hundred (and increasingly grows beyond
nr_dentry_unused).

Tweak the logic in the paths that turn a dentry negative or positive
to filter out the case where the dentry is present on a shrink
related list. This allows the above workload to maintain an accurate
negative dentry count.

Fixes: af0c9af1

 ("fs/dcache: Track & report number of negative dentries")
Signed-off-by: Brian Foster <bfoster@redhat.com>
Link: https://lore.kernel.org/r/20240703121301.247680-1-bfoster@redhat.com


Acked-by: Ian Kent <ikent@redhat.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Light Hsieh reported a KASAN UAF warning in trace_posix_lock_inode().
The request pointer had been changed earlier to point to a lock entry
that was added to the inode's list. However, before the tracepoint could
fire, another task raced in and freed that lock.

Fix this by moving the tracepoint inside the spinlock, which should
ensure that this doesn't happen.

Fixes: 74f6f591 ("locks: fix KASAN: use-after-free in trace_event_raw_event_filelock_lock")
Link: https://lore.kernel.org/linux-fsdevel/724ffb0a2962e912ea62bb0515deadf39c325112.camel@kernel.org/


Reported-by: Light Hsieh (謝明燈) <Light.Hsieh@mediatek.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240702-filelock-6-10-v1-1-96e766aadc98@kernel.org


Reviewed-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

libaokun@huaweicloud.com <libaokun@huaweicloud.com> says:

This is the third version of this patch series, in which another patch set
is subsumed into this one to avoid confusing the two patch sets.
(https://patchwork.kernel.org/project/linux-fsdevel/list/?series=854914)

We've been testing ondemand mode for cachefiles since January, and we're
almost done. We hit a lot of issues during the testing period, and this
patch series fixes some of the issues. The patches have passed internal
testing without regression.

The following is a brief overview of the patches, see the patches for
more details.

Patch 1-2: Add fscache_try_get_volume() helper function to avoid
fscache_volume use-after-free on cache withdrawal.

Patch 3: Fix cachefiles_lookup_cookie() and cachefiles_withdraw_cache()
concurrency causing cachefiles_volume use-after-free.

Patch 4: Propagate error codes returned by vfs_getxattr() to avoid
endless loops.

Patch 5-7: A read request waiting for re...

Add missing lock protection in poll routine when iterating xarray,
otherwise:

Even with RCU read lock held, only the slot of the radix tree is
ensured to be pinned there, while the data structure (e.g. struct
cachefiles_req) stored in the slot has no such guarantee.  The poll
routine will iterate the radix tree and dereference cachefiles_req
accordingly.  Thus RCU read lock is not adequate in this case and
spinlock is needed here.

Fixes: b817e22b

 ("cachefiles: narrow the scope of triggering EPOLLIN events in ondemand mode")
Signed-off-by: Jingbo Xu <jefflexu@linux.alibaba.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-10-libaokun@huaweicloud.com


Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Reusing the msg_id after a maliciously completed reopen request may cause
a read request to remain unprocessed and result in a hung, as shown below:

       t1       |      t2       |      t3
-------------------------------------------------
cachefiles_ondemand_select_req
 cachefiles_ondemand_object_is_close(A)
 cachefiles_ondemand_set_object_reopening(A)
 queue_work(fscache_object_wq, &info->work)
                ondemand_object_worker
                 cachefiles_ondemand_init_object(A)
                  cachefiles_ondemand_send_req(OPEN)
                    // get msg_id 6
                    wait_for_completion(&req_A->done)
cachefiles_ondemand_daemon_read
 // read msg_id 6 req_A
 cachefiles_ondemand_get_fd
 copy_to_user
                                // Malicious completion msg_id 6
                                copen 6,-1
                                cachefiles_ondemand_copen
                                 complete(&req_A->done)
                                 // will not set the object to close
                                 // because ondemand_id && fd is valid.

                // ondemand_object_worker() is done
                // but the object is still reopening.

                                // new open req_B
                                cachefiles_ondemand_init_object(B)
                                 cachefiles_ondemand_send_req(OPEN)
                                 // reuse msg_id 6
process_open_req
 copen 6,A.size
 // The expected failed copen was executed successfully

Expect copen to fail, and when it does, it closes fd, which sets the
object to close, and then close triggers reopen again. However, due to
msg_id reuse resulting in a successful copen, the anonymous fd is not
closed until the daemon exits. Therefore read requests waiting for reopen
to complete may trigger hung task.

To avoid this issue, allocate the msg_id cyclically to avoid reusing the
msg_id for a very short duration of time.

Fixes: c8383054

 ("cachefiles: notify the user daemon when looking up cookie")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-9-libaokun@huaweicloud.com


Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

When queuing ondemand_object_worker() to re-open the object,
cachefiles_object is not pinned. The cachefiles_object may be freed when
the pending read request is completed intentionally and the related
erofs is umounted. If ondemand_object_worker() runs after the object is
freed, it will incur use-after-free problem as shown below.

process A  processs B  process C  process D

cachefiles_ondemand_send_req()
// send a read req X
// wait for its completion

           // close ondemand fd
           cachefiles_ondemand_fd_release()
           // set object as CLOSE

                       cachefiles_ondemand_daemon_read()
                       // set object as REOPENING
                       queue_work(fscache_wq, &info->ondemand_work)

                                // close /dev/cachefiles
                                cachefiles_daemon_release
                                cachefiles_flush_reqs
                                complete(&req->done)

// read req X is completed
// umount the erofs fs
cachefiles_put_object()
// object will be freed
cachefiles_ondemand_deinit_obj_info()
kmem_cache_free(object)
                       // both info and object are freed
                       ondemand_object_worker()

When dropping an object, it is no longer necessary to reopen the object,
so use cancel_work_sync() to cancel or wait for ondemand_object_worker()
to finish.

Fixes: 0a7e54c1

 ("cachefiles: resend an open request if the read request's object is closed")
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-8-libaokun@huaweicloud.com


Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Because after an object is dropped, requests for that object are useless,
cancel them to avoid causing other problems.

This prepares for the later addition of cancel_work_sync(). After the
reopen requests is generated, cancel it to avoid cancel_work_sync()
blocking by waiting for daemon to complete the reopen requests.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-7-libaokun@huaweicloud.com


Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Added CACHEFILES_ONDEMAND_OBJSTATE_DROPPING indicates that the cachefiles
object is being dropped, and is set after the close request for the dropped
object completes, and no new requests are allowed to be sent after this
state.

This prepares for the later addition of cancel_work_sync(). It prevents
leftover reopen requests from being sent, to avoid processing unnecessary
requests and to avoid cancel_work_sync() blocking by waiting for daemon to
complete the reopen requests.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-6-libaokun@huaweicloud.com


Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Reviewed-by: Jia Zhu <zhujia.zj@bytedance.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

In cachefiles_check_volume_xattr(), the error returned by vfs_getxattr()
is not passed to ret, so it ends up returning -ESTALE, which leads to an
endless loop as follows:

cachefiles_acquire_volume
retry:
  ret = cachefiles_check_volume_xattr
    ret = -ESTALE
    xlen = vfs_getxattr // return -EIO
    // The ret is not updated when xlen < 0, so -ESTALE is returned.
    return ret
  // Supposed to jump out of the loop at this judgement.
  if (ret != -ESTALE)
      goto error_dir;
  cachefiles_bury_object
    //  EIO causes rename failure
  goto retry;

Hence propagate the error returned by vfs_getxattr() to avoid the above
issue. Do the same in cachefiles_check_auxdata().

Fixes: 32e15003 ("fscache, cachefiles: Store the volume coherency data")
Fixes: 72b95785

 ("cachefiles: Implement metadata/coherency data storage in xattrs")
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.246799...

We got the following issue in our fault injection stress test:

==================================================================
BUG: KASAN: slab-use-after-free in cachefiles_withdraw_cookie+0x4d9/0x600
Read of size 8 at addr ffff888118efc000 by task kworker/u78:0/109

CPU: 13 PID: 109 Comm: kworker/u78:0 Not tainted 6.8.0-dirty #566
Call Trace:
 <TASK>
 kasan_report+0x93/0xc0
 cachefiles_withdraw_cookie+0x4d9/0x600
 fscache_cookie_state_machine+0x5c8/0x1230
 fscache_cookie_worker+0x91/0x1c0
 process_one_work+0x7fa/0x1800
 [...]

Allocated by task 117:
 kmalloc_trace+0x1b3/0x3c0
 cachefiles_acquire_volume+0xf3/0x9c0
 fscache_create_volume_work+0x97/0x150
 process_one_work+0x7fa/0x1800
 [...]

Freed by task 120301:
 kfree+0xf1/0x2c0
 cachefiles_withdraw_cache+0x3fa/0x920
 cachefiles_put_unbind_pincount+0x1f6/0x250
 cachefiles_daemon_release+0x13b/0x290
 __fput+0x204/0xa00
 task_work_run+0x139/0x230
 do_exit+0x87a/0x29b0
 [...]
==========...

We got the following issue in our fault injection stress test:

==================================================================
BUG: KASAN: slab-use-after-free in fscache_withdraw_volume+0x2e1/0x370
Read of size 4 at addr ffff88810680be08 by task ondemand-04-dae/5798

CPU: 0 PID: 5798 Comm: ondemand-04-dae Not tainted 6.8.0-dirty #565
Call Trace:
 kasan_check_range+0xf6/0x1b0
 fscache_withdraw_volume+0x2e1/0x370
 cachefiles_withdraw_volume+0x31/0x50
 cachefiles_withdraw_cache+0x3ad/0x900
 cachefiles_put_unbind_pincount+0x1f6/0x250
 cachefiles_daemon_release+0x13b/0x290
 __fput+0x204/0xa00
 task_work_run+0x139/0x230

Allocated by task 5820:
 __kmalloc+0x1df/0x4b0
 fscache_alloc_volume+0x70/0x600
 __fscache_acquire_volume+0x1c/0x610
 erofs_fscache_register_volume+0x96/0x1a0
 erofs_fscache_register_fs+0x49a/0x690
 erofs_fc_fill_super+0x6c0/0xcc0
 vfs_get_super+0xa9/0x140
 vfs_get_tree+0x8e/0x300
 do_new_mount+0x28c/0x580
 [...]

Freed by tas...

Export fscache_put_volume() and add fscache_try_get_volume()
helper function to allow cachefiles to get/put fscache_volume
via linux/fscache-cache.h.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Link: https://lore.kernel.org/r/20240628062930.2467993-2-libaokun@huaweicloud.com


Signed-off-by: Christian Brauner <brauner@kernel.org>

Pull ata fixes from Niklas Cassel:

 - Add NOLPM quirk for for all Crucial BX SSD1 models.

   Considering that we now have had bug reports for 3 different BX SSD1
   variants from Crucial with the same product name, make the quirk more
   inclusive, to catch more device models from the same generation.

 - Fix a trivial NULL pointer dereference in the error path for
   ata_host_release().

 - Create a ata_port_free(), so that we don't miss freeing ata_port
   struct members when freeing a struct ata_port.

 - Fix a trivial double free in the error path for ata_host_alloc().

 - Ensure that we remove the libata "remapped NVMe device count" sysfs
   entry on .probe() error.

* tag 'ata-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/libata/linux:
  ata: ahci: Clean up sysfs file on error
  ata: libata-core: Fix double free on error
  ata,scsi: libata-core: Do not leak memory for ata_port struct members
  ata: libata-core: Fix null pointer dereference on error
  ata: libata-core: Add ATA_HORKAGE_NOLPM for all Crucial BX SSD1 models

.probe() (ahci_init_one()) calls sysfs_add_file_to_group(), however,
if probe() fails after this call, we currently never call
sysfs_remove_file_from_group().

(The sysfs_remove_file_from_group() call in .remove() (ahci_remove_one())
does not help, as .remove() is not called on .probe() error.)

Thus, if probe() fails after the sysfs_add_file_to_group() call, the next
time we insmod the module we will get:

sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:04.0/remapped_nvme'
CPU: 11 PID: 954 Comm: modprobe Not tainted 6.10.0-rc5 #43
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x5d/0x80
 sysfs_warn_dup.cold+0x17/0x23
 sysfs_add_file_mode_ns+0x11a/0x130
 sysfs_add_file_to_group+0x7e/0xc0
 ahci_init_one+0x31f/0xd40 [ahci]

Fixes: 894fba7f

 ("ata: ahci: Add sysfs attribute to show remapped NVMe device count")
Cc: stable@vger.kernel.org
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240629124210.181537-10-cassel@kernel.org


Signed-off-by: Niklas Cassel <cassel@kernel.org>

If e.g. the ata_port_alloc() call in ata_host_alloc() fails, we will jump
to the err_out label, which will call devres_release_group().
devres_release_group() will trigger a call to ata_host_release().
ata_host_release() calls kfree(host), so executing the kfree(host) in
ata_host_alloc() will lead to a double free:

kernel BUG at mm/slub.c:553!
Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
CPU: 11 PID: 599 Comm: (udev-worker) Not tainted 6.10.0-rc5 #47
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
RIP: 0010:kfree+0x2cf/0x2f0
Code: 5d 41 5e 41 5f 5d e9 80 d6 ff ff 4d 89 f1 41 b8 01 00 00 00 48 89 d9 48 89 da
RSP: 0018:ffffc90000f377f0 EFLAGS: 00010246
RAX: ffff888112b1f2c0 RBX: ffff888112b1f2c0 RCX: ffff888112b1f320
RDX: 000000000000400b RSI: ffffffffc02c9de5 RDI: ffff888112b1f2c0
RBP: ffffc90000f37830 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90000f37610 R11: 617461203a736b6e R12: ffffea00044ac780
R13: ffff888100046400 R14: ffffffffc02c9de5 R15: 0000000000000006
FS:  00007f2f1cabe980(0000) GS:ffff88813b380000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2f1c3acf75 CR3: 0000000111724000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
 <TASK>
 ? __die_body.cold+0x19/0x27
 ? die+0x2e/0x50
 ? do_trap+0xca/0x110
 ? do_error_trap+0x6a/0x90
 ? kfree+0x2cf/0x2f0
 ? exc_invalid_op+0x50/0x70
 ? kfree+0x2cf/0x2f0
 ? asm_exc_invalid_op+0x1a/0x20
 ? ata_host_alloc+0xf5/0x120 [libata]
 ? ata_host_alloc+0xf5/0x120 [libata]
 ? kfree+0x2cf/0x2f0
 ata_host_alloc+0xf5/0x120 [libata]
 ata_host_alloc_pinfo+0x14/0xa0 [libata]
 ahci_init_one+0x6c9/0xd20 [ahci]

Ensure that we will not call kfree(host) twice, by performing the kfree()
only if the devres_open_group() call failed.

Fixes: dafd6c49

 ("libata: ensure host is free'd on error exit paths")
Cc: stable@vger.kernel.org
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240629124210.181537-9-cassel@kernel.org


Signed-off-by: Niklas Cassel <cassel@kernel.org>

libsas is currently not freeing all the struct ata_port struct members,
e.g. ncq_sense_buf for a driver supporting Command Duration Limits (CDL).

Add a function, ata_port_free(), that is used to free a ata_port,
including its struct members. It makes sense to keep the code related to
freeing a ata_port in its own function, which will also free all the
struct members of struct ata_port.

Fixes: 18bd7718

 ("scsi: ata: libata: Handle completion of CDL commands using policy 0xD")
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240629124210.181537-8-cassel@kernel.org


Signed-off-by: Niklas Cassel <cassel@kernel.org>

If the ata_port_alloc() call in ata_host_alloc() fails,
ata_host_release() will get called.

However, the code in ata_host_release() tries to free ata_port struct
members unconditionally, which can lead to the following:

BUG: unable to handle page fault for address: 0000000000003990
PGD 0 P4D 0
Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI
CPU: 10 PID: 594 Comm: (udev-worker) Not tainted 6.10.0-rc5 #44
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
RIP: 0010:ata_host_release.cold+0x2f/0x6e [libata]
Code: e4 4d 63 f4 44 89 e2 48 c7 c6 90 ad 32 c0 48 c7 c7 d0 70 33 c0 49 83 c6 0e 41
RSP: 0018:ffffc90000ebb968 EFLAGS: 00010246
RAX: 0000000000000041 RBX: ffff88810fb52e78 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88813b3218c0 RDI: ffff88813b3218c0
RBP: ffff88810fb52e40 R08: 0000000000000000 R09: 6c65725f74736f68
R10: ffffc90000ebb738 R11: 73692033203a746e R12: 0000000000000004
R13: 0000000000000000 R14: 0000000000000011 R15: 0000000000000006
FS:  00007f6cc55b9980(0000) GS:ffff88813b300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000003990 CR3: 00000001122a2000 CR4: 0000000000750ef0
PKRU: 55555554
Call Trace:
 <TASK>
 ? __die_body.cold+0x19/0x27
 ? page_fault_oops+0x15a/0x2f0
 ? exc_page_fault+0x7e/0x180
 ? asm_exc_page_fault+0x26/0x30
 ? ata_host_release.cold+0x2f/0x6e [libata]
 ? ata_host_release.cold+0x2f/0x6e [libata]
 release_nodes+0x35/0xb0
 devres_release_group+0x113/0x140
 ata_host_alloc+0xed/0x120 [libata]
 ata_host_alloc_pinfo+0x14/0xa0 [libata]
 ahci_init_one+0x6c9/0xd20 [ahci]

Do not access ata_port struct members unconditionally.

Fixes: 633273a3

 ("libata-pmp: hook PMP support and enable it")
Cc: stable@vger.kernel.org
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20240629124210.181537-7-cassel@kernel.org


Signed-off-by: Niklas Cassel <cassel@kernel.org>

Merge tag 'kbuild-fixes-v6.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Remove the executable bit from installed DTB files

 - Escape $ in subshell execution in the debian-orig target

 - Fix RPM builds with CONFIG_MODULES=n

 - Fix xconfig with the O= option

 - Fix scripts_gdb with the O= option

* tag 'kbuild-fixes-v6.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: scripts/gdb: bring the "abspath" back
  kbuild: Use $(obj)/%.cc to fix host C++ module builds
  kbuild: rpm-pkg: fix build error with CONFIG_MODULES=n
  kbuild: Fix build target deb-pkg: ln: failed to create hard link
  kbuild: doc: Update default INSTALL_MOD_DIR from extra to updates
  kbuild: Install dtb files as 0644 in Makefile.dtbinst

The kernel test robot reported that clang no longer compiles the 32-bit
x86 kernel in some configurations due to commit 95ece481


("locking/atomic/x86: Rewrite x86_32 arch_atomic64_{,fetch}_{and,or,xor}()
functions").

The build fails with

  arch/x86/include/asm/cmpxchg_32.h:149:9: error: inline assembly requires more registers than available

and the reason seems to be that not only does the cmpxchg8b instruction
need four fixed registers (EDX:EAX and ECX:EBX), with the emulation
fallback the inline asm also wants a fifth fixed register for the
address (it uses %esi for that, but that's just a software convention
with cmpxchg8b_emu).

Avoiding using another pointer input to the asm (and just forcing it to
use the "0(%esi)" addressing that we end up requiring for the sw
fallback) seems to fix the issue.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202406230912.F6XFIyA6-lkp@intel.com/
Fixes: 95ece481 ("locking/atomic/x86: Rewrite x86_32 arch_atomic64_{,fetch}_{and,or,xor}() functions")
Link: https://lore.kernel.org/all/202406230912.F6XFIyA6-lkp@intel.com/


Suggested-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-and-Tested-by: Uros Bizjak <ubizjak@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull char/misc driver fixes from Greg KH:
 "Here are some small driver fixes for 6.10-rc6. Included in here are:

   - IIO driver fixes for reported issues

   - Counter driver fix for a reported problem.

  All of these have been in linux-next this week with no reported
  issues"

* tag 'char-misc-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  counter: ti-eqep: enable clock at probe
  iio: chemical: bme680: Fix sensor data read operation
  iio: chemical: bme680: Fix overflows in compensate() functions
  iio: chemical: bme680: Fix calibration data variable
  iio: chemical: bme680: Fix pressure value output
  iio: humidity: hdc3020: fix hysteresis representation
  iio: dac: fix ad9739a random config compile error
  iio: accel: fxls8962af: select IIO_BUFFER & IIO_KFIFO_BUF
  iio: adc: ad7266: Fix variable checking bug
  iio: xilinx-ams: Don't include ams_ctrl_channels in scan_mask

Pull staging driver fixes from Greg KH:
 "Here are two small staging driver fixes for 6.10-rc6, both for the
  vc04_services drivers:

   - build fix if CONFIG_DEBUGFS was not set

   - initialization check fix that was much reported.

  Both of these have been in linux-next this week with no reported
  issues"

* tag 'staging-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  staging: vchiq_debugfs: Fix build if CONFIG_DEBUG_FS is not set
  staging: vc04_services: vchiq_arm: Fix initialisation check

Pull tty / serial / console fixes from Greg KH:
 "Here are a bunch of fixes/reverts for 6.10-rc6.  Include in here are:

   - revert the bunch of tty/serial/console changes that landed in -rc1
     that didn't quite work properly yet.

     Everyone agreed to just revert them for now and will work on making
     them better for a future release instead of trying to quick fix the
     existing changes this late in the release cycle

   - 8250 driver port count bugfix

   - Other tiny serial port bugfixes for reported issues

  All of these have been in linux-next this week with no reported
  issues"

* tag 'tty-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "printk: Save console options for add_preferred_console_match()"
  Revert "printk: Don't try to parse DEVNAME:0.0 console options"
  Revert "printk: Flag register_console() if console is set on command line"
  Revert "serial: core: Add support for DEVNAME:0.0 style naming for kernel console"
  Revert "serial: core: Handle serial console options"
  Revert "serial: 8250: Add preferred console in serial8250_isa_init_ports()"
  Revert "Documentation: kernel-parameters: Add DEVNAME:0.0 format for serial ports"
  Revert "serial: 8250: Fix add preferred console for serial8250_isa_init_ports()"
  Revert "serial: core: Fix ifdef for serial base console functions"
  serial: bcm63xx-uart: fix tx after conversion to uart_port_tx_limited()
  serial: core: introduce uart_port_tx_limited_flags()
  Revert "serial: core: only stop transmit when HW fifo is empty"
  serial: imx: set receiver level before starting uart
  tty: mcf: MCF54418 has 10 UARTS
  serial: 8250_omap: Implementation of Errata i2310
  tty: serial: 8250: Fix port count mismatch with the device

Pull USB fixes from Greg KH:
 "Here are a handful of small USB driver fixes for 6.10-rc6 to resolve
  some reported issues. Included in here are:

   - typec driver bugfixes

   - usb gadget driver reverts for commits that were reported to have
     problems

   - resource leak bugfix

   - gadget driver bugfixes

   - dwc3 driver bugfixes

   - usb atm driver bugfix for when syzbot got loose on it

  All of these have been in linux-next this week with no reported issues"

* tag 'usb-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  usb: dwc3: core: Workaround for CSR read timeout
  Revert "usb: gadget: u_ether: Replace netif_stop_queue with netif_device_detach"
  Revert "usb: gadget: u_ether: Re-attach netif device to mirror detachment"
  usb: gadget: aspeed_udc: fix device address configuration
  usb: dwc3: core: remove lock of otg mode during gadget suspend/resume to avoid deadlock
  usb: typec: ucsi: glink: fix child node release in probe function
  usb: musb: da8xx: fix a resource leak in probe()
  usb: typec: ucsi_acpi: Add LG Gram quirk
  usb: ucsi: stm32: fix command completion handling
  usb: atm: cxacru: fix endpoint checking in cxacru_bind()
  usb: gadget: printer: fix races against disable
  usb: gadget: printer: SS+ support

Pull smp fixes from Borislav Petkov:

 - Fix "nosmp" and "maxcpus=0" after the parallel CPU bringup work went
   in and broke them

 - Make sure CPU hotplug dynamic prepare states are actually executed

* tag 'smp_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu: Fix broken cmdline "nosmp" and "maxcpus=0"
  cpu/hotplug: Fix dynstate assignment in __cpuhp_setup_state_cpuslocked()

Pull irq fixes from Borislav Petkov:

 - Make sure multi-bridge machines get all eiointc interrupt controllers
   initialized even if the number of CPUs has been limited by a cmdline
   param

 - Make sure interrupt lines on liointc hw are configured properly even
   when interrupt routing changes

 - Avoid use-after-free in the error path of the MSI init code

* tag 'irq_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  PCI/MSI: Fix UAF in msi_capability_init
  irqchip/loongson-liointc: Set different ISRs for different cores
  irqchip/loongson-eiointc: Use early_cpu_to_node() instead of cpu_to_node()

Pull timer fix from Borislav Petkov:

 - Warn when an hrtimer doesn't get a callback supplied

* tag 'timers_urgent_for_v6.10_rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  hrtimer: Prevent queuing of hrtimer without a function callback

Pull watchdog fixes from Wim Van Sebroeck:

 - lenovo_se10_wdt: add HAS_IOPORT dependency

 - add missing MODULE_DESCRIPTION() macros

* tag 'linux-watchdog-6.10-rc-fixes' of git://www.linux-watchdog.org/linux-watchdog:
  watchdog: add missing MODULE_DESCRIPTION() macros
  watchdog: lenovo_se10_wdt: add HAS_IOPORT dependency

Pull NFS client fix from Trond Myklebust:

 - One more SUNRPC fix for the NFSv4.x backchannel timeouts

* tag 'nfs-for-6.10-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
  SUNRPC: Fix backchannel reply, again

Pull xfs fixes from Chandan Babu:

 - Always free only post-EOF delayed allocations for files with the
   XFS_DIFLAG_PREALLOC or APPEND flags set.

 - Do not align cow fork delalloc to cowextsz hint when running low on
   space.

 - Allow zero-size symlinks and directories as long as the link count is
   zero.

 - Change XFS_IOC_EXCHANGE_RANGE to be a _IOW only ioctl. This was ioctl
   was introduced during v6.10 developement cycle.

 - xfs_init_new_inode() now creates an attribute fork on a newly created
   inode even if ATTR feature flag is not enabled.

* tag 'xfs-6.10-fixes-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: honor init_xattrs in xfs_init_new_inode for !ATTR fs
  xfs: fix direction in XFS_IOC_EXCHANGE_RANGE
  xfs: allow unlinked symlinks and dirs with zero size
  xfs: restrict when we try to align cow fork delalloc to cowextsz hints
  xfs: fix freeing speculative preallocations for preallocated files

Pull i2c fixes from Wolfram Sang:
 "Two fixes for the testunit and and a fixup for the code reorganization
  of the previous wmt-driver"

* tag 'i2c-for-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: testunit: discard write requests while old command is running
  i2c: testunit: don't erase registers after STOP
  i2c: viai2c: turn common code into a proper module

Merge tag 'platform-drivers-x86-v6.10-4' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

Pull x86 platform driver fixes from Hans de Goede:

 - Fix lg-laptop driver not working with 2024 LG laptop models

 - Add missing MODULE_DESCRIPTION() macros to various modules

 - nvsw-sn2201: Add check for platform_device_add_resources

* tag 'platform-drivers-x86-v6.10-4' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: add missing MODULE_DESCRIPTION() macros
  platform/x86/intel: add missing MODULE_DESCRIPTION() macros
  platform/x86/siemens: add missing MODULE_DESCRIPTION() macros
  platform/x86: lg-laptop: Use ACPI device handle when evaluating WMAB/WMBB
  platform/x86: lg-laptop: Change ACPI device id
  platform/x86: lg-laptop: Remove LGEX0815 hotkey handling
  platform/x86: wireless-hotkey: Add support for LG Airplane Button
  platform/mellanox: nvsw-sn2201: Add check for platform_device_add_resources

Pull MMC fixes from Ulf Hansson:

 - moxart-mmc: Revert "mmc: moxart-mmc: Use sg_miter for PIO"

 - sdhci: Do not invert write-protect twice

 - sdhci: Do not lock spinlock around mmc_gpio_get_ro()

 - sdhci-pci/sdhci-pci-o2micro: Return proper error codes

 - sdhci-brcmstb: Fix support for erase/trim/discard

* tag 'mmc-v6.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc:
  mmc: sdhci: Do not lock spinlock around mmc_gpio_get_ro()
  mmc: sdhci: Do not invert write-protect twice
  Revert "mmc: moxart-mmc: Use sg_miter for PIO"
  mmc: sdhci-brcmstb: check R1_STATUS for erase/trim/discard
  mmc: sdhci-pci-o2micro: Convert PCIBIOS_* return codes to errnos
  mmc: sdhci-pci: Convert PCIBIOS_* return codes to errnos

Pull RISC-V fixes from Palmer Dabbelt:

 - A fix for vector load/store instruction decoding, which could result
   in reserved vector element length encodings decoding as valid vector
   instructions.

 - Instruction patching now aggressively flushes the local instruction
   cache, to avoid situations where patching functions on the flush path
   results in torn instructions being fetched.

 - A fix to prevent the stack walker from showing up as part of traces.

* tag 'riscv-for-linus-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: stacktrace: convert arch_stack_walk() to noinstr
  riscv: patch: Flush the icache right after patching to avoid illegal insns
  RISC-V: fix vector insn load/store width mask

Pull hardening fixes from Kees Cook:

 - Remove invalid tty __counted_by annotation (Nathan Chancellor)

 - Add missing MODULE_DESCRIPTION()s for KUnit string tests (Jeff
   Johnson)

 - Remove non-functional per-arch kstack entropy filtering

* tag 'hardening-v6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  tty: mxser: Remove __counted_by from mxser_board.ports[]
  randomize_kstack: Remove non-functional per-arch entropy filtering
  string: kunit: add missing MODULE_DESCRIPTION() macros

The 'profile_pc()' function is used for timer-based profiling, which
isn't really all that relevant any more to begin with, but it also ends
up making assumptions based on the stack layout that aren't necessarily
valid.

Basically, the code tries to account the time spent in spinlocks to the
caller rather than the spinlock, and while I support that as a concept,
it's not worth the code complexity or the KASAN warnings when no serious
profiling is done using timers anyway these days.

And the code really does depend on stack layout that is only true in the
simplest of cases.  We've lost the comment at some point (I think when
the 32-bit and 64-bit code was unified), but it used to say:

	Assume the lock function has either no stack frame or a copy
	of eflags from PUSHF.

which explains why it just blindly loads a word or two straight off the
stack pointer and then takes a minimal look at the values to just check
if they might be eflags or the return pc:

	Eflags always has bits 22 and up cleared unlike kernel addresses

but that basic stack layout assumption assumes that there isn't any lock
debugging etc going on that would complicate the code and cause a stack
frame.

It causes KASAN unhappiness reported for years by syzkaller [1] and
others [2].

With no real practical reason for this any more, just remove the code.

Just for historical interest, here's some background commits relating to
this code from 2006:

  0cb91a22 ("i386: Account spinlocks to the caller during profiling for !FP kernels")
  31679f38 ("Simplify profile_pc on x86-64")

and a code unification from 2009:

  ef451288 ("x86: time_32/64.c unify profile_pc")

but the basics of this thing actually goes back to before the git tree.

Link: https://syzkaller.appspot.com/bug?extid=84fe685c02cd112a2ac3 [1]
Link: https://lore.kernel.org/all/CAK55_s7Xyq=nh97=K=G1sxueOFrJDAvPOJAL4TPTCAYvmxO9_A@mail.gmail.com/

 [2]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When clearing registers on new write requests was added, the protection
for currently running commands was missed leading to concurrent access
to the testunit registers. Check the flag beforehand.

Fixes: b39ab96a

 ("i2c: testunit: add support for block process calls")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>

STOP fallsthrough to WRITE_REQUESTED but this became problematic when
clearing the testunit registers was added to the latter. Actually, there
is no reason to clear the testunit state after STOP. Doing it when a new
WRITE_REQUESTED arrives is enough. So, no need to fallthrough, at all.

Fixes: b39ab96a

 ("i2c: testunit: add support for block process calls")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>

Merge tag 'i2c-host-fixes-6.10-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-current

Fixed a build error following the major refactoring involving the
VIA-I2C modules. Originally, the code was split to group together
parts that would be used by different drivers. This caused build
issues when two modules linked to the same code.

Pull nfsd fixes from Chuck Lever:

 - Due to a late review, revert and re-fix a recent crasher fix

* tag 'nfsd-6.10-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux:
  Revert "nfsd: fix oops when reading pool_stats before server is started"
  nfsd: initialise nfsd_info.mutex early.