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Bump jinja2 from 3.1.3 to 3.1.4 in /Documentation/sphinx #3

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@dependabot dependabot bot commented on behalf of github May 6, 2024

Bumps jinja2 from 3.1.3 to 3.1.4.

Release notes

Sourced from jinja2's releases.

3.1.4

This is the Jinja 3.1.4 security release, which fixes security issues and bugs but does not otherwise change behavior and should not result in breaking changes.

PyPI: https://pypi.org/project/Jinja2/3.1.4/ Changes: https://jinja.palletsprojects.com/en/3.1.x/changes/#version-3-1-4

  • The xmlattr filter does not allow keys with / solidus, > greater-than sign, or = equals sign, in addition to disallowing spaces. Regardless of any validation done by Jinja, user input should never be used as keys to this filter, or must be separately validated first. GHSA-h75v-3vvj-5mfj
Changelog

Sourced from jinja2's changelog.

Version 3.1.4

Released 2024-05-05

  • The xmlattr filter does not allow keys with / solidus, > greater-than sign, or = equals sign, in addition to disallowing spaces. Regardless of any validation done by Jinja, user input should never be used as keys to this filter, or must be separately validated first. :ghsa:h75v-3vvj-5mfj
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Bumps [jinja2](https://github.com/pallets/jinja) from 3.1.3 to 3.1.4.
- [Release notes](https://github.com/pallets/jinja/releases)
- [Changelog](https://github.com/pallets/jinja/blob/main/CHANGES.rst)
- [Commits](pallets/jinja@3.1.3...3.1.4)

---
updated-dependencies:
- dependency-name: jinja2
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
@dependabot dependabot bot added the dependencies Pull requests that update a dependency file label May 6, 2024
@sysopenci
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Improper Commit Message
Tracked on not found in commit message,
make sure Tracked-On: Jira-ticket is present.

sysopenci pushed a commit that referenced this pull request Aug 4, 2024
[ Upstream commit f8bbc07ac535593139c875ffa19af924b1084540 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <[email protected]>
Reviewed-by: Willem de Bruijn <[email protected]>
Acked-by: Jason Wang <[email protected]>
Reviewed-by: Eric Dumazet <[email protected]>
Acked-by: Michael S. Tsirkin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
sysopenci pushed a commit that referenced this pull request Aug 4, 2024
commit 9e985cbf2942a1bb8fcef9adc2a17d90fd7ca8ee upstream.

Drop support for virtualizing adaptive PEBS, as KVM's implementation is
architecturally broken without an obvious/easy path forward, and because
exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak
host kernel addresses to the guest.

Bug #1 is that KVM doesn't account for the upper 32 bits of
IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g
fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters()
stores local variables as u8s and truncates the upper bits too, etc.

Bug #2 is that, because KVM _always_ sets precise_ip to a non-zero value
for PEBS events, perf will _always_ generate an adaptive record, even if
the guest requested a basic record.  Note, KVM will also enable adaptive
PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the
guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero,
i.e. the guest will only ever see Basic records.

Bug #3 is in perf.  intel_pmu_disable_fixed() doesn't clear the upper
bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and
intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE
either.  I.e. perf _always_ enables ADAPTIVE counters, regardless of what
KVM requests.

Bug #4 is that adaptive PEBS *might* effectively bypass event filters set
by the host, as "Updated Memory Access Info Group" records information
that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER.

Bug #5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least
zeros) when entering a vCPU with adaptive PEBS, which allows the guest
to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries"
records.

Disable adaptive PEBS support as an immediate fix due to the severity of
the LBR leak in particular, and because fixing all of the bugs will be
non-trivial, e.g. not suitable for backporting to stable kernels.

Note!  This will break live migration, but trying to make KVM play nice
with live migration would be quite complicated, wouldn't be guaranteed to
work (i.e. KVM might still kill/confuse the guest), and it's not clear
that there are any publicly available VMMs that support adaptive PEBS,
let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't
support PEBS in any capacity.

Link: https://lore.kernel.org/all/[email protected]
Link: https://lore.kernel.org/all/[email protected]
Fixes: c59a1f1 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
Cc: [email protected]
Cc: Like Xu <[email protected]>
Cc: Mingwei Zhang <[email protected]>
Cc: Zhenyu Wang <[email protected]>
Cc: Zhang Xiong <[email protected]>
Cc: Lv Zhiyuan <[email protected]>
Cc: Dapeng Mi <[email protected]>
Cc: Jim Mattson <[email protected]>
Acked-by: Like Xu <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
sysopenci pushed a commit that referenced this pull request Aug 4, 2024
commit 1983184c22dd84a4d95a71e5c6775c2638557dc7 upstream.

When I did hard offline test with hugetlb pages, below deadlock occurs:

======================================================
WARNING: possible circular locking dependency detected
6.8.0-11409-gf6cef5f8c37f #1 Not tainted
------------------------------------------------------
bash/46904 is trying to acquire lock:
ffffffffabe68910 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_slow_dec+0x16/0x60

but task is already holding lock:
ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #1 (pcp_batch_high_lock){+.+.}-{3:3}:
       __mutex_lock+0x6c/0x770
       page_alloc_cpu_online+0x3c/0x70
       cpuhp_invoke_callback+0x397/0x5f0
       __cpuhp_invoke_callback_range+0x71/0xe0
       _cpu_up+0xeb/0x210
       cpu_up+0x91/0xe0
       cpuhp_bringup_mask+0x49/0xb0
       bringup_nonboot_cpus+0xb7/0xe0
       smp_init+0x25/0xa0
       kernel_init_freeable+0x15f/0x3e0
       kernel_init+0x15/0x1b0
       ret_from_fork+0x2f/0x50
       ret_from_fork_asm+0x1a/0x30

-> #0 (cpu_hotplug_lock){++++}-{0:0}:
       __lock_acquire+0x1298/0x1cd0
       lock_acquire+0xc0/0x2b0
       cpus_read_lock+0x2a/0xc0
       static_key_slow_dec+0x16/0x60
       __hugetlb_vmemmap_restore_folio+0x1b9/0x200
       dissolve_free_huge_page+0x211/0x260
       __page_handle_poison+0x45/0xc0
       memory_failure+0x65e/0xc70
       hard_offline_page_store+0x55/0xa0
       kernfs_fop_write_iter+0x12c/0x1d0
       vfs_write+0x387/0x550
       ksys_write+0x64/0xe0
       do_syscall_64+0xca/0x1e0
       entry_SYSCALL_64_after_hwframe+0x6d/0x75

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(pcp_batch_high_lock);
                               lock(cpu_hotplug_lock);
                               lock(pcp_batch_high_lock);
  rlock(cpu_hotplug_lock);

 *** DEADLOCK ***

5 locks held by bash/46904:
 #0: ffff98f6c3bb23f0 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x64/0xe0
 #1: ffff98f6c328e488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0xf8/0x1d0
 #2: ffff98ef83b31890 (kn->active#113){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x100/0x1d0
 #3: ffffffffabf9db48 (mf_mutex){+.+.}-{3:3}, at: memory_failure+0x44/0xc70
 #4: ffffffffabf92ea8 (pcp_batch_high_lock){+.+.}-{3:3}, at: zone_pcp_disable+0x16/0x40

stack backtrace:
CPU: 10 PID: 46904 Comm: bash Kdump: loaded Not tainted 6.8.0-11409-gf6cef5f8c37f #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x68/0xa0
 check_noncircular+0x129/0x140
 __lock_acquire+0x1298/0x1cd0
 lock_acquire+0xc0/0x2b0
 cpus_read_lock+0x2a/0xc0
 static_key_slow_dec+0x16/0x60
 __hugetlb_vmemmap_restore_folio+0x1b9/0x200
 dissolve_free_huge_page+0x211/0x260
 __page_handle_poison+0x45/0xc0
 memory_failure+0x65e/0xc70
 hard_offline_page_store+0x55/0xa0
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x387/0x550
 ksys_write+0x64/0xe0
 do_syscall_64+0xca/0x1e0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fc862314887
Code: 10 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b7 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007fff19311268 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007fc862314887
RDX: 000000000000000c RSI: 000056405645fe10 RDI: 0000000000000001
RBP: 000056405645fe10 R08: 00007fc8623d1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 00007fc86241b780 R14: 00007fc862417600 R15: 00007fc862416a00

In short, below scene breaks the lock dependency chain:

 memory_failure
  __page_handle_poison
   zone_pcp_disable -- lock(pcp_batch_high_lock)
   dissolve_free_huge_page
    __hugetlb_vmemmap_restore_folio
     static_key_slow_dec
      cpus_read_lock -- rlock(cpu_hotplug_lock)

Fix this by calling drain_all_pages() instead.

This issue won't occur until commit a6b4085 ("mm: hugetlb: replace
hugetlb_free_vmemmap_enabled with a static_key").  As it introduced
rlock(cpu_hotplug_lock) in dissolve_free_huge_page() code path while
lock(pcp_batch_high_lock) is already in the __page_handle_poison().

[[email protected]: extend comment per Oscar]
[[email protected]: reflow block comment]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: a6b4085 ("mm: hugetlb: replace hugetlb_free_vmemmap_enabled with a static_key")
Signed-off-by: Miaohe Lin <[email protected]>
Acked-by: Oscar Salvador <[email protected]>
Reviewed-by: Jane Chu <[email protected]>
Cc: Naoya Horiguchi <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
sysopenci pushed a commit that referenced this pull request Aug 4, 2024
…io()

commit 52ccdde16b6540abe43b6f8d8e1e1ec90b0983af upstream.

When I did memory failure tests recently, below warning occurs:

DEBUG_LOCKS_WARN_ON(1)
WARNING: CPU: 8 PID: 1011 at kernel/locking/lockdep.c:232 __lock_acquire+0xccb/0x1ca0
Modules linked in: mce_inject hwpoison_inject
CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
RIP: 0010:__lock_acquire+0xccb/0x1ca0
RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082
RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8
RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0
RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb
R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10
R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004
FS:  00007ff9f32aa740(0000) GS:ffffa1ce5fc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ff9f3134ba0 CR3: 00000008484e4000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0xbe/0x2d0
 _raw_spin_lock_irqsave+0x3a/0x60
 hugepage_subpool_put_pages.part.0+0xe/0xc0
 free_huge_folio+0x253/0x3f0
 dissolve_free_huge_page+0x147/0x210
 __page_handle_poison+0x9/0x70
 memory_failure+0x4e6/0x8c0
 hard_offline_page_store+0x55/0xa0
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x380/0x540
 ksys_write+0x64/0xe0
 do_syscall_64+0xbc/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9f3114887
RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887
RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001
RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00
 </TASK>
Kernel panic - not syncing: kernel: panic_on_warn set ...
CPU: 8 PID: 1011 Comm: bash Kdump: loaded Not tainted 6.9.0-rc3-next-20240410-00012-gdb69f219f4be #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
Call Trace:
 <TASK>
 panic+0x326/0x350
 check_panic_on_warn+0x4f/0x50
 __warn+0x98/0x190
 report_bug+0x18e/0x1a0
 handle_bug+0x3d/0x70
 exc_invalid_op+0x18/0x70
 asm_exc_invalid_op+0x1a/0x20
RIP: 0010:__lock_acquire+0xccb/0x1ca0
RSP: 0018:ffffa7a1c7fe3bd0 EFLAGS: 00000082
RAX: 0000000000000000 RBX: eb851eb853975fcf RCX: ffffa1ce5fc1c9c8
RDX: 00000000ffffffd8 RSI: 0000000000000027 RDI: ffffa1ce5fc1c9c0
RBP: ffffa1c6865d3280 R08: ffffffffb0f570a8 R09: 0000000000009ffb
R10: 0000000000000286 R11: ffffffffb0f2ad50 R12: ffffa1c6865d3d10
R13: ffffa1c6865d3c70 R14: 0000000000000000 R15: 0000000000000004
 lock_acquire+0xbe/0x2d0
 _raw_spin_lock_irqsave+0x3a/0x60
 hugepage_subpool_put_pages.part.0+0xe/0xc0
 free_huge_folio+0x253/0x3f0
 dissolve_free_huge_page+0x147/0x210
 __page_handle_poison+0x9/0x70
 memory_failure+0x4e6/0x8c0
 hard_offline_page_store+0x55/0xa0
 kernfs_fop_write_iter+0x12c/0x1d0
 vfs_write+0x380/0x540
 ksys_write+0x64/0xe0
 do_syscall_64+0xbc/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff9f3114887
RSP: 002b:00007ffecbacb458 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 000000000000000c RCX: 00007ff9f3114887
RDX: 000000000000000c RSI: 0000564494164e10 RDI: 0000000000000001
RBP: 0000564494164e10 R08: 00007ff9f31d1460 R09: 000000007fffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000000c
R13: 00007ff9f321b780 R14: 00007ff9f3217600 R15: 00007ff9f3216a00
 </TASK>

After git bisecting and digging into the code, I believe the root cause is
that _deferred_list field of folio is unioned with _hugetlb_subpool field.
In __update_and_free_hugetlb_folio(), folio->_deferred_list is
initialized leading to corrupted folio->_hugetlb_subpool when folio is
hugetlb.  Later free_huge_folio() will use _hugetlb_subpool and above
warning happens.

But it is assumed hugetlb flag must have been cleared when calling
folio_put() in update_and_free_hugetlb_folio().  This assumption is broken
due to below race:

CPU1					CPU2
dissolve_free_huge_page			update_and_free_pages_bulk
 update_and_free_hugetlb_folio		 hugetlb_vmemmap_restore_folios
					  folio_clear_hugetlb_vmemmap_optimized
  clear_flag = folio_test_hugetlb_vmemmap_optimized
  if (clear_flag) <-- False, it's already cleared.
   __folio_clear_hugetlb(folio) <-- Hugetlb is not cleared.
  folio_put
   free_huge_folio <-- free_the_page is expected.
					 list_for_each_entry()
					  __folio_clear_hugetlb <-- Too late.

Fix this issue by checking whether folio is hugetlb directly instead of
checking clear_flag to close the race window.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 32c8771 ("hugetlb: do not clear hugetlb dtor until allocating vmemmap")
Signed-off-by: Miaohe Lin <[email protected]>
Reviewed-by: Oscar Salvador <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Miaohe Lin <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
sysopenci pushed a commit that referenced this pull request Aug 4, 2024
[ Upstream commit 118e021 ]

When we reserve a delalloc region in xfs_buffered_write_iomap_begin,
we mark the iomap as IOMAP_F_NEW so that the the write context
understands that it allocated the delalloc region.

If we then fail that buffered write, xfs_buffered_write_iomap_end()
checks for the IOMAP_F_NEW flag and if it is set, it punches out
the unused delalloc region that was allocated for the write.

The assumption this code makes is that all buffered write operations
that can allocate space are run under an exclusive lock (i_rwsem).
This is an invalid assumption: page faults in mmap()d regions call
through this same function pair to map the file range being faulted
and this runs only holding the inode->i_mapping->invalidate_lock in
shared mode.

IOWs, we can have races between page faults and write() calls that
fail the nested page cache write operation that result in data loss.
That is, the failing iomap_end call will punch out the data that
the other racing iomap iteration brought into the page cache. This
can be reproduced with generic/34[46] if we arbitrarily fail page
cache copy-in operations from write() syscalls.

Code analysis tells us that the iomap_page_mkwrite() function holds
the already instantiated and uptodate folio locked across the iomap
mapping iterations. Hence the folio cannot be removed from memory
whilst we are mapping the range it covers, and as such we do not
care if the mapping changes state underneath the iomap iteration
loop:

1. if the folio is not already dirty, there is no writeback races
   possible.
2. if we allocated the mapping (delalloc or unwritten), the folio
   cannot already be dirty. See #1.
3. If the folio is already dirty, it must be up to date. As we hold
   it locked, it cannot be reclaimed from memory. Hence we always
   have valid data in the page cache while iterating the mapping.
4. Valid data in the page cache can exist when the underlying
   mapping is DELALLOC, UNWRITTEN or WRITTEN. Having the mapping
   change from DELALLOC->UNWRITTEN or UNWRITTEN->WRITTEN does not
   change the data in the page - it only affects actions if we are
   initialising a new page. Hence #3 applies  and we don't care
   about these extent map transitions racing with
   iomap_page_mkwrite().
5. iomap_page_mkwrite() checks for page invalidation races
   (truncate, hole punch, etc) after it locks the folio. We also
   hold the mapping->invalidation_lock here, and hence the mapping
   cannot change due to extent removal operations while we are
   iterating the folio.

As such, filesystems that don't use bufferheads will never fail
the iomap_folio_mkwrite_iter() operation on the current mapping,
regardless of whether the iomap should be considered stale.

Further, the range we are asked to iterate is limited to the range
inside EOF that the folio spans. Hence, for XFS, we will only map
the exact range we are asked for, and we will only do speculative
preallocation with delalloc if we are mapping a hole at the EOF
page. The iterator will consume the entire range of the folio that
is within EOF, and anything beyond the EOF block cannot be accessed.
We never need to truncate this post-EOF speculative prealloc away in
the context of the iomap_page_mkwrite() iterator because if it
remains unused we'll remove it when the last reference to the inode
goes away.

Hence we don't actually need an .iomap_end() cleanup/error handling
path at all for iomap_page_mkwrite() for XFS. This means we can
separate the page fault processing from the complexity of the
.iomap_end() processing in the buffered write path. This also means
that the buffered write path will also be able to take the
mapping->invalidate_lock as necessary.

Signed-off-by: Dave Chinner <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Reviewed-by: Darrick J. Wong <[email protected]>
Signed-off-by: Leah Rumancik <[email protected]>
Acked-by: Darrick J. Wong <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
@sysopenci sysopenci added the Stale Stale label for inactive open prs label Sep 5, 2024
JeevakaPrabu pushed a commit that referenced this pull request Sep 23, 2024
commit 22f00812862564b314784167a89f27b444f82a46 upstream.

The syzbot fuzzer found that the interrupt-URB completion callback in
the cdc-wdm driver was taking too long, and the driver's immediate
resubmission of interrupt URBs with -EPROTO status combined with the
dummy-hcd emulation to cause a CPU lockup:

cdc_wdm 1-1:1.0: nonzero urb status received: -71
cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes
watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625]
CPU#0 Utilization every 4s during lockup:
	#1:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#2:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#3:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#4:  98% system,	  0% softirq,	  3% hardirq,	  0% idle
	#5:  98% system,	  1% softirq,	  3% hardirq,	  0% idle
Modules linked in:
irq event stamp: 73096
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline]
hardirqs last  enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994
hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline]
hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551
softirqs last  enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline]
softirqs last  enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582
softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588
CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G        W          6.10.0-rc2-syzkaller-g8867bbd4a056 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024

Testing showed that the problem did not occur if the two error
messages -- the first two lines above -- were removed; apparently adding
material to the kernel log takes a surprisingly large amount of time.

In any case, the best approach for preventing these lockups and to
avoid spamming the log with thousands of error messages per second is
to ratelimit the two dev_err() calls.  Therefore we replace them with
dev_err_ratelimited().

Signed-off-by: Alan Stern <[email protected]>
Suggested-by: Greg KH <[email protected]>
Reported-and-tested-by: [email protected]
Closes: https://lore.kernel.org/linux-usb/[email protected]/
Reported-and-tested-by: [email protected]
Closes: https://lore.kernel.org/linux-usb/[email protected]/
Fixes: 9908a32 ("USB: remove err() macro from usb class drivers")
Link: https://lore.kernel.org/linux-usb/[email protected]/
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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