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Pre merge CI workflow

Signed-off-by: Vishal Kumar <viskuma@qti.qualcomm.com>
shashim-quic pushed a commit that referenced this pull request Jun 10, 2025
syzkaller has found another ugly race in the VGIC, this time dealing
with VGIC creation. Since kvm_vgic_create() doesn't sufficiently protect
against in-flight vCPU creations, it is possible to get a vCPU into the
kernel w/ an in-kernel VGIC but no allocation of private IRQs:

  Unable to handle kernel NULL pointer dereference at virtual address 0000000000000d20
  Mem abort info:
    ESR = 0x0000000096000046
    EC = 0x25: DABT (current EL), IL = 32 bits
    SET = 0, FnV = 0
    EA = 0, S1PTW = 0
    FSC = 0x06: level 2 translation fault
  Data abort info:
    ISV = 0, ISS = 0x00000046, ISS2 = 0x00000000
    CM = 0, WnR = 1, TnD = 0, TagAccess = 0
    GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
  user pgtable: 4k pages, 48-bit VAs, pgdp=0000000103e4f000
  [0000000000000d20] pgd=0800000102e1c403, p4d=0800000102e1c403, pud=0800000101146403, pmd=0000000000000000
  Internal error: Oops: 0000000096000046 [#1] PREEMPT SMP
  CPU: 9 UID: 0 PID: 246 Comm: test Not tainted 6.14.0-rc6-00097-g0c90821f5db8 #16
  Hardware name: linux,dummy-virt (DT)
  pstate: 814020c5 (Nzcv daIF +PAN -UAO -TCO +DIT -SSBS BTYPE=--)
  pc : _raw_spin_lock_irqsave+0x34/0x8c
  lr : kvm_vgic_set_owner+0x54/0xa4
  sp : ffff80008086ba20
  x29: ffff80008086ba20 x28: ffff0000c19b5640 x27: 0000000000000000
  x26: 0000000000000000 x25: ffff0000c4879bd0 x24: 000000000000001e
  x23: 0000000000000000 x22: 0000000000000000 x21: ffff0000c487af80
  x20: ffff0000c487af18 x19: 0000000000000000 x18: 0000001afadd5a8b
  x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000001
  x14: ffff0000c19b56c0 x13: 0030c9adf9d9889e x12: ffffc263710e1908
  x11: 0000001afb0d74f2 x10: e0966b840b373664 x9 : ec806bf7d6a57cd5
  x8 : ffff80008086b980 x7 : 0000000000000001 x6 : 0000000000000001
  x5 : 0000000080800054 x4 : 4ec4ec4ec4ec4ec5 x3 : 0000000000000000
  x2 : 0000000000000001 x1 : 0000000000000000 x0 : 0000000000000d20
  Call trace:
   _raw_spin_lock_irqsave+0x34/0x8c (P)
   kvm_vgic_set_owner+0x54/0xa4
   kvm_timer_enable+0xf4/0x274
   kvm_arch_vcpu_run_pid_change+0xe0/0x380
   kvm_vcpu_ioctl+0x93c/0x9e0
   __arm64_sys_ioctl+0xb4/0xec
   invoke_syscall+0x48/0x110
   el0_svc_common.constprop.0+0x40/0xe0
   do_el0_svc+0x1c/0x28
   el0_svc+0x30/0xd0
   el0t_64_sync_handler+0x10c/0x138
   el0t_64_sync+0x198/0x19c
   Code: b9000841 d503201f 52800001 52800022 (88e17c02)
   ---[ end trace 0000000000000000 ]---

Plug the race by explicitly checking for an in-progress vCPU creation
and failing kvm_vgic_create() when that's the case. Add some comments to
document all the things kvm_vgic_create() is trying to guard against
too.

Reported-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Tested-by: Alexander Potapenko <glider@google.com>
Link: https://lore.kernel.org/r/20250523194722.4066715-6-oliver.upton@linux.dev
Signed-off-by: Marc Zyngier <maz@kernel.org>
vdadhani pushed a commit to vdadhani/kernel-topics that referenced this pull request Jun 12, 2025
There is a potential deadlock if we do report zones in an IO context, detailed
in below lockdep report. When one process do a report zones and another process
freezes the block device, the report zones side cannot allocate a tag because
the freeze is already started. This can thus result in new block group creation
to hang forever, blocking the write path.

Thankfully, a new block group should be created on empty zones. So, reporting
the zones is not necessary and we can set the write pointer = 0 and load the
zone capacity from the block layer using bdev_zone_capacity() helper.

 ======================================================
 WARNING: possible circular locking dependency detected
 6.14.0-rc1 qualcomm-linux#252 Not tainted
 ------------------------------------------------------
 modprobe/1110 is trying to acquire lock:
 ffff888100ac83e0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0x38f/0xb60

 but task is already holding lock:
 ffff8881205b6f20 (&q->q_usage_counter(queue)qualcomm-linux#16){++++}-{0:0}, at: sd_remove+0x85/0x130

 which lock already depends on the new lock.

 the existing dependency chain (in reverse order) is:

 -> qualcomm-linux#3 (&q->q_usage_counter(queue)qualcomm-linux#16){++++}-{0:0}:
        blk_queue_enter+0x3d9/0x500
        blk_mq_alloc_request+0x47d/0x8e0
        scsi_execute_cmd+0x14f/0xb80
        sd_zbc_do_report_zones+0x1c1/0x470
        sd_zbc_report_zones+0x362/0xd60
        blkdev_report_zones+0x1b1/0x2e0
        btrfs_get_dev_zones+0x215/0x7e0 [btrfs]
        btrfs_load_block_group_zone_info+0x6d2/0x2c10 [btrfs]
        btrfs_make_block_group+0x36b/0x870 [btrfs]
        btrfs_create_chunk+0x147d/0x2320 [btrfs]
        btrfs_chunk_alloc+0x2ce/0xcf0 [btrfs]
        start_transaction+0xce6/0x1620 [btrfs]
        btrfs_uuid_scan_kthread+0x4ee/0x5b0 [btrfs]
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> qualcomm-linux#2 (&fs_info->dev_replace.rwsem){++++}-{4:4}:
        down_read+0x9b/0x470
        btrfs_map_block+0x2ce/0x2ce0 [btrfs]
        btrfs_submit_chunk+0x2d4/0x16c0 [btrfs]
        btrfs_submit_bbio+0x16/0x30 [btrfs]
        btree_write_cache_pages+0xb5a/0xf90 [btrfs]
        do_writepages+0x17f/0x7b0
        __writeback_single_inode+0x114/0xb00
        writeback_sb_inodes+0x52b/0xe00
        wb_writeback+0x1a7/0x800
        wb_workfn+0x12a/0xbd0
        process_one_work+0x85a/0x1460
        worker_thread+0x5e2/0xfc0
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> qualcomm-linux#1 (&fs_info->zoned_meta_io_lock){+.+.}-{4:4}:
        __mutex_lock+0x1aa/0x1360
        btree_write_cache_pages+0x252/0xf90 [btrfs]
        do_writepages+0x17f/0x7b0
        __writeback_single_inode+0x114/0xb00
        writeback_sb_inodes+0x52b/0xe00
        wb_writeback+0x1a7/0x800
        wb_workfn+0x12a/0xbd0
        process_one_work+0x85a/0x1460
        worker_thread+0x5e2/0xfc0
        kthread+0x39d/0x750
        ret_from_fork+0x30/0x70
        ret_from_fork_asm+0x1a/0x30

 -> #0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}:
        __lock_acquire+0x2f52/0x5ea0
        lock_acquire+0x1b1/0x540
        __flush_work+0x3ac/0xb60
        wb_shutdown+0x15b/0x1f0
        bdi_unregister+0x172/0x5b0
        del_gendisk+0x841/0xa20
        sd_remove+0x85/0x130
        device_release_driver_internal+0x368/0x520
        bus_remove_device+0x1f1/0x3f0
        device_del+0x3bd/0x9c0
        __scsi_remove_device+0x272/0x340
        scsi_forget_host+0xf7/0x170
        scsi_remove_host+0xd2/0x2a0
        sdebug_driver_remove+0x52/0x2f0 [scsi_debug]
        device_release_driver_internal+0x368/0x520
        bus_remove_device+0x1f1/0x3f0
        device_del+0x3bd/0x9c0
        device_unregister+0x13/0xa0
        sdebug_do_remove_host+0x1fb/0x290 [scsi_debug]
        scsi_debug_exit+0x17/0x70 [scsi_debug]
        __do_sys_delete_module.isra.0+0x321/0x520
        do_syscall_64+0x93/0x180
        entry_SYSCALL_64_after_hwframe+0x76/0x7e

 other info that might help us debug this:

 Chain exists of:
   (work_completion)(&(&wb->dwork)->work) --> &fs_info->dev_replace.rwsem --> &q->q_usage_counter(queue)qualcomm-linux#16

  Possible unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(&q->q_usage_counter(queue)qualcomm-linux#16);
                                lock(&fs_info->dev_replace.rwsem);
                                lock(&q->q_usage_counter(queue)qualcomm-linux#16);
   lock((work_completion)(&(&wb->dwork)->work));

  *** DEADLOCK ***

 5 locks held by modprobe/1110:
  #0: ffff88811f7bc108 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520
  qualcomm-linux#1: ffff8881022ee0e0 (&shost->scan_mutex){+.+.}-{4:4}, at: scsi_remove_host+0x20/0x2a0
  qualcomm-linux#2: ffff88811b4c4378 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0x8f/0x520
  qualcomm-linux#3: ffff8881205b6f20 (&q->q_usage_counter(queue)qualcomm-linux#16){++++}-{0:0}, at: sd_remove+0x85/0x130
  qualcomm-linux#4: ffffffffa3284360 (rcu_read_lock){....}-{1:3}, at: __flush_work+0xda/0xb60

 stack backtrace:
 CPU: 0 UID: 0 PID: 1110 Comm: modprobe Not tainted 6.14.0-rc1 qualcomm-linux#252
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014
 Call Trace:
  <TASK>
  dump_stack_lvl+0x6a/0x90
  print_circular_bug.cold+0x1e0/0x274
  check_noncircular+0x306/0x3f0
  ? __pfx_check_noncircular+0x10/0x10
  ? mark_lock+0xf5/0x1650
  ? __pfx_check_irq_usage+0x10/0x10
  ? lockdep_lock+0xca/0x1c0
  ? __pfx_lockdep_lock+0x10/0x10
  __lock_acquire+0x2f52/0x5ea0
  ? __pfx___lock_acquire+0x10/0x10
  ? __pfx_mark_lock+0x10/0x10
  lock_acquire+0x1b1/0x540
  ? __flush_work+0x38f/0xb60
  ? __pfx_lock_acquire+0x10/0x10
  ? __pfx_lock_release+0x10/0x10
  ? mark_held_locks+0x94/0xe0
  ? __flush_work+0x38f/0xb60
  __flush_work+0x3ac/0xb60
  ? __flush_work+0x38f/0xb60
  ? __pfx_mark_lock+0x10/0x10
  ? __pfx___flush_work+0x10/0x10
  ? __pfx_wq_barrier_func+0x10/0x10
  ? __pfx___might_resched+0x10/0x10
  ? mark_held_locks+0x94/0xe0
  wb_shutdown+0x15b/0x1f0
  bdi_unregister+0x172/0x5b0
  ? __pfx_bdi_unregister+0x10/0x10
  ? up_write+0x1ba/0x510
  del_gendisk+0x841/0xa20
  ? __pfx_del_gendisk+0x10/0x10
  ? _raw_spin_unlock_irqrestore+0x35/0x60
  ? __pm_runtime_resume+0x79/0x110
  sd_remove+0x85/0x130
  device_release_driver_internal+0x368/0x520
  ? kobject_put+0x5d/0x4a0
  bus_remove_device+0x1f1/0x3f0
  device_del+0x3bd/0x9c0
  ? __pfx_device_del+0x10/0x10
  __scsi_remove_device+0x272/0x340
  scsi_forget_host+0xf7/0x170
  scsi_remove_host+0xd2/0x2a0
  sdebug_driver_remove+0x52/0x2f0 [scsi_debug]
  ? kernfs_remove_by_name_ns+0xc0/0xf0
  device_release_driver_internal+0x368/0x520
  ? kobject_put+0x5d/0x4a0
  bus_remove_device+0x1f1/0x3f0
  device_del+0x3bd/0x9c0
  ? __pfx_device_del+0x10/0x10
  ? __pfx___mutex_unlock_slowpath+0x10/0x10
  device_unregister+0x13/0xa0
  sdebug_do_remove_host+0x1fb/0x290 [scsi_debug]
  scsi_debug_exit+0x17/0x70 [scsi_debug]
  __do_sys_delete_module.isra.0+0x321/0x520
  ? __pfx___do_sys_delete_module.isra.0+0x10/0x10
  ? __pfx_slab_free_after_rcu_debug+0x10/0x10
  ? kasan_save_stack+0x2c/0x50
  ? kasan_record_aux_stack+0xa3/0xb0
  ? __call_rcu_common.constprop.0+0xc4/0xfb0
  ? kmem_cache_free+0x3a0/0x590
  ? __x64_sys_close+0x78/0xd0
  do_syscall_64+0x93/0x180
  ? lock_is_held_type+0xd5/0x130
  ? __call_rcu_common.constprop.0+0x3c0/0xfb0
  ? lockdep_hardirqs_on+0x78/0x100
  ? __call_rcu_common.constprop.0+0x3c0/0xfb0
  ? __pfx___call_rcu_common.constprop.0+0x10/0x10
  ? kmem_cache_free+0x3a0/0x590
  ? lockdep_hardirqs_on_prepare+0x16d/0x400
  ? do_syscall_64+0x9f/0x180
  ? lockdep_hardirqs_on+0x78/0x100
  ? do_syscall_64+0x9f/0x180
  ? __pfx___x64_sys_openat+0x10/0x10
  ? lockdep_hardirqs_on_prepare+0x16d/0x400
  ? do_syscall_64+0x9f/0x180
  ? lockdep_hardirqs_on+0x78/0x100
  ? do_syscall_64+0x9f/0x180
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7f436712b68b
 RSP: 002b:00007ffe9f1a8658 EFLAGS: 00000206 ORIG_RAX: 00000000000000b0
 RAX: ffffffffffffffda RBX: 00005559b367fd80 RCX: 00007f436712b68b
 RDX: 0000000000000000 RSI: 0000000000000800 RDI: 00005559b367fde8
 RBP: 00007ffe9f1a8680 R08: 1999999999999999 R09: 0000000000000000
 R10: 00007f43671a5fe0 R11: 0000000000000206 R12: 0000000000000000
 R13: 00007ffe9f1a86b0 R14: 0000000000000000 R15: 0000000000000000
  </TASK>

Reported-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
CC: <stable@vger.kernel.org> # 6.13+
Tested-by: Shin'ichiro Kawasaki <shinichiro.kawasaki@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Signed-off-by: David Sterba <dsterba@suse.com>
sgaud-quic pushed a commit that referenced this pull request Oct 15, 2025
The pm_domain cleanup can not be devres managed as it uses struct
simplefb_par which is allocated within struct fb_info by
framebuffer_alloc(). This allocation is explicitly freed by
unregister_framebuffer() in simplefb_remove().
Devres managed cleanup runs after the device remove call and thus can no
longer access struct simplefb_par.
Call simplefb_detach_genpds() explicitly from simplefb_destroy() like
the cleanup functions for clocks and regulators.

Fixes an use after free on M2 Mac mini during
aperture_remove_conflicting_devices() using the downstream asahi kernel
with Debian's kernel config. For unknown reasons this started to
consistently dereference an invalid pointer in v6.16.3 based kernels.

[    6.736134] BUG: KASAN: slab-use-after-free in simplefb_detach_genpds+0x58/0x220
[    6.743545] Read of size 4 at addr ffff8000304743f0 by task (udev-worker)/227
[    6.750697]
[    6.752182] CPU: 6 UID: 0 PID: 227 Comm: (udev-worker) Tainted: G S                  6.16.3-asahi+ #16 PREEMPTLAZY
[    6.752186] Tainted: [S]=CPU_OUT_OF_SPEC
[    6.752187] Hardware name: Apple Mac mini (M2, 2023) (DT)
[    6.752189] Call trace:
[    6.752190]  show_stack+0x34/0x98 (C)
[    6.752194]  dump_stack_lvl+0x60/0x80
[    6.752197]  print_report+0x17c/0x4d8
[    6.752201]  kasan_report+0xb4/0x100
[    6.752206]  __asan_report_load4_noabort+0x20/0x30
[    6.752209]  simplefb_detach_genpds+0x58/0x220
[    6.752213]  devm_action_release+0x50/0x98
[    6.752216]  release_nodes+0xd0/0x2c8
[    6.752219]  devres_release_all+0xfc/0x178
[    6.752221]  device_unbind_cleanup+0x28/0x168
[    6.752224]  device_release_driver_internal+0x34c/0x470
[    6.752228]  device_release_driver+0x20/0x38
[    6.752231]  bus_remove_device+0x1b0/0x380
[    6.752234]  device_del+0x314/0x820
[    6.752238]  platform_device_del+0x3c/0x1e8
[    6.752242]  platform_device_unregister+0x20/0x50
[    6.752246]  aperture_detach_platform_device+0x1c/0x30
[    6.752250]  aperture_detach_devices+0x16c/0x290
[    6.752253]  aperture_remove_conflicting_devices+0x34/0x50
...
[    6.752343]
[    6.967409] Allocated by task 62:
[    6.970724]  kasan_save_stack+0x3c/0x70
[    6.974560]  kasan_save_track+0x20/0x40
[    6.978397]  kasan_save_alloc_info+0x40/0x58
[    6.982670]  __kasan_kmalloc+0xd4/0xd8
[    6.986420]  __kmalloc_noprof+0x194/0x540
[    6.990432]  framebuffer_alloc+0xc8/0x130
[    6.994444]  simplefb_probe+0x258/0x2378
...
[    7.054356]
[    7.055838] Freed by task 227:
[    7.058891]  kasan_save_stack+0x3c/0x70
[    7.062727]  kasan_save_track+0x20/0x40
[    7.066565]  kasan_save_free_info+0x4c/0x80
[    7.070751]  __kasan_slab_free+0x6c/0xa0
[    7.074675]  kfree+0x10c/0x380
[    7.077727]  framebuffer_release+0x5c/0x90
[    7.081826]  simplefb_destroy+0x1b4/0x2c0
[    7.085837]  put_fb_info+0x98/0x100
[    7.089326]  unregister_framebuffer+0x178/0x320
[    7.093861]  simplefb_remove+0x3c/0x60
[    7.097611]  platform_remove+0x60/0x98
[    7.101361]  device_remove+0xb8/0x160
[    7.105024]  device_release_driver_internal+0x2fc/0x470
[    7.110256]  device_release_driver+0x20/0x38
[    7.114529]  bus_remove_device+0x1b0/0x380
[    7.118628]  device_del+0x314/0x820
[    7.122116]  platform_device_del+0x3c/0x1e8
[    7.126302]  platform_device_unregister+0x20/0x50
[    7.131012]  aperture_detach_platform_device+0x1c/0x30
[    7.136157]  aperture_detach_devices+0x16c/0x290
[    7.140779]  aperture_remove_conflicting_devices+0x34/0x50
...

Reported-by: Daniel Huhardeaux <tech@tootai.net>
Cc: stable@vger.kernel.org
Fixes: 92a511a ("fbdev/simplefb: Add support for generic power-domains")
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Hans de Goede <hansg@kernel.org>
Signed-off-by: Helge Deller <deller@gmx.de>
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