Skip to content

L
linux
Switch branch/tag
  1. 15 Apr, 2024 1 commit
    • Dave Airlie's avatar
      nouveau: fix instmem race condition around ptr stores · fff1386c
      Dave Airlie authored 
      Running a lot of VK CTS in parallel against nouveau, once every
few hours you might see something like this crash.

BUG: kernel NULL pointer dereference, address: 0000000000000008
PGD 8000000114e6e067 P4D 8000000114e6e067 PUD 109046067 PMD 0
Oops: 0000 [#1] PREEMPT SMP PTI
CPU: 7 PID: 53891 Comm: deqp-vk Not tainted 6.8.0-rc6+ #27
Hardware name: Gigabyte Technology Co., Ltd. Z390 I AORUS PRO WIFI/Z390 I AORUS PRO WIFI-CF, BIOS F8 11/05/2021
RIP: 0010:gp100_vmm_pgt_mem+0xe3/0x180 [nouveau]
Code: c7 48 01 c8 49 89 45 58 85 d2 0f 84 95 00 00 00 41 0f b7 46 12 49 8b 7e 08 89 da 42 8d 2c f8 48 8b 47 08 41 83 c7 01 48 89 ee <48> 8b 40 08 ff d0 0f 1f 00 49 8b 7e 08 48 89 d9 48 8d 75 04 48 c1
RSP: 0000:ffffac20c5857838 EFLAGS: 00010202
RAX: 0000000000000000 RBX: 00000000004d8001 RCX: 0000000000000001
RDX: 00000000004d8001 RSI: 00000000000006d8 RDI: ffffa07afe332180
RBP: 00000000000006d8 R08: ffffac20c5857ad0 R09: 0000000000ffff10
R10: 0000000000000001 R11: ffffa07af27e2de0 R12: 000000000000001c
R13: ffffac20c5857ad0 R14: ffffa07a96fe9040 R15: 000000000000001c
FS:  00007fe395eed7c0(0000) GS:ffffa07e2c980000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000008 CR3: 000000011febe001 CR4: 00000000003706f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:

...

 ? gp100_vmm_pgt_mem+0xe3/0x180 [nouveau]
 ? gp100_vmm_pgt_mem+0x37/0x180 [nouveau]
 nvkm_vmm_iter+0x351/0xa20 [nouveau]
 ? __pfx_nvkm_vmm_ref_ptes+0x10/0x10 [nouveau]
 ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau]
 ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau]
 ? __lock_acquire+0x3ed/0x2170
 ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau]
 nvkm_vmm_ptes_get_map+0xc2/0x100 [nouveau]
 ? __pfx_nvkm_vmm_ref_ptes+0x10/0x10 [nouveau]
 ? __pfx_gp100_vmm_pgt_mem+0x10/0x10 [nouveau]
 nvkm_vmm_map_locked+0x224/0x3a0 [nouveau]

Adding any sort of useful debug usually makes it go away, so I hand
wrote the function in a line, and debugged the asm.

Every so often pt->memory->ptrs is NULL. This ptrs ptr is set in
the nv50_instobj_acquire called from nvkm_kmap.

If Thread A and Thread B both get to nv50_instobj_acquire around
the same time, and Thread A hits the refcount_set line, and in
lockstep thread B succeeds at refcount_inc_not_zero, there is a
chance the ptrs value won't have been stored since refcount_set
is unordered. Force a memory barrier here, I picked smp_mb, since
we want it on all CPUs and it's write followed by a read.

v2: use paired smp_rmb/smp_wmb.

Cc: <stable@vger.kernel.org>
Fixes: be55287a ("drm/nouveau/imem/nv50: embed nvkm_instobj directly into nv04_instobj")
Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
Signed-off-by: default avatarDanilo Krummrich <dakr@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240411011510.2546857-1-airlied@gmail.com
      fff1386c
  3. 09 Apr, 2024 1 commit
  5. 08 Apr, 2024 10 commits
  7. 05 Apr, 2024 4 commits
  9. 04 Apr, 2024 1 commit
  11. 01 Apr, 2024 1 commit
  13. 28 Mar, 2024 6 commits
  15. 27 Mar, 2024 1 commit
    • Jocelyn Falempe's avatar
      drm/vmwgfx: Create debugfs ttm_resource_manager entry only if needed · 4be9075f
      Jocelyn Falempe authored 
      The driver creates /sys/kernel/debug/dri/0/mob_ttm even when the
corresponding ttm_resource_manager is not allocated.
This leads to a crash when trying to read from this file.

Add a check to create mob_ttm, system_mob_ttm, and gmr_ttm debug file
only when the corresponding ttm_resource_manager is allocated.

crash> bt
PID: 3133409  TASK: ffff8fe4834a5000  CPU: 3    COMMAND: "grep"
 #0 [ffffb954506b3b20] machine_kexec at ffffffffb2a6bec3
 #1 [ffffb954506b3b78] __crash_kexec at ffffffffb2bb598a
 #2 [ffffb954506b3c38] crash_kexec at ffffffffb2bb68c1
 #3 [ffffb954506b3c50] oops_end at ffffffffb2a2a9b1
 #4 [ffffb954506b3c70] no_context at ffffffffb2a7e913
 #5 [ffffb954506b3cc8] __bad_area_nosemaphore at ffffffffb2a7ec8c
 #6 [ffffb954506b3d10] do_page_fault at ffffffffb2a7f887
 #7 [ffffb954506b3d40] page_fault at ffffffffb360116e
    [exception RIP: ttm_resource_manager_debug+0x11]
    RIP: ffffffffc04afd11  RSP: ffffb954506b3df0  RFLAGS: 00010246
    RAX: ffff8fe41a6d1200  RBX: 0000000000000000  RCX: 0000000000000940
    RDX: 0000000000000000  RSI: ffffffffc04b4338  RDI: 0000000000000000
    RBP: ffffb954506b3e08   R8: ffff8fee3ffad000   R9: 0000000000000000
    R10: ffff8fe41a76a000  R11: 0000000000000001  R12: 00000000ffffffff
    R13: 0000000000000001  R14: ffff8fe5bb6f3900  R15: ffff8fe41a6d1200
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffb954506b3e00] ttm_resource_manager_show at ffffffffc04afde7 [ttm]
 #9 [ffffb954506b3e30] seq_read at ffffffffb2d8f9f3
    RIP: 00007f4c4eda8985  RSP: 00007ffdbba9e9f8  RFLAGS: 00000246
    RAX: ffffffffffffffda  RBX: 000000000037e000  RCX: 00007f4c4eda8985
    RDX: 000000000037e000  RSI: 00007f4c41573000  RDI: 0000000000000003
    RBP: 000000000037e000   R8: 0000000000000000   R9: 000000000037fe30
    R10: 0000000000000000  R11: 0000000000000246  R12: 00007f4c41573000
    R13: 0000000000000003  R14: 00007f4c41572010  R15: 0000000000000003
    ORIG_RAX: 0000000000000000  CS: 0033  SS: 002b
Signed-off-by: default avatarJocelyn Falempe <jfalempe@redhat.com>
Fixes: af4a25bb ("drm/vmwgfx: Add debugfs entries for various ttm resource managers")
Cc: <stable@vger.kernel.org>
Reviewed-by: default avatarZack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240312093551.196609-1-jfalempe@redhat.com
      4be9075f
  17. 26 Mar, 2024 1 commit
  19. 25 Mar, 2024 2 commits
  21. 24 Mar, 2024 12 commits
    • Linus Torvalds's avatar
      Linux 6.9-rc1 · 4cece764
      Linus Torvalds authored
      4cece764
    • Linus Torvalds's avatar
      Merge tag 'efi-fixes-for-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi · ab8de2db
      Linus Torvalds authored 
      Pull EFI fixes from Ard Biesheuvel:

 - Fix logic that is supposed to prevent placement of the kernel image
   below LOAD_PHYSICAL_ADDR

 - Use the firmware stack in the EFI stub when running in mixed mode

 - Clear BSS only once when using mixed mode

 - Check efi.get_variable() function pointer for NULL before trying to
   call it

* tag 'efi-fixes-for-v6.9-2' of git://git.kernel.org/pub/scm/linux/kernel/git/efi/efi:
  efi: fix panic in kdump kernel
  x86/efistub: Don't clear BSS twice in mixed mode
  x86/efistub: Call mixed mode boot services on the firmware's stack
  efi/libstub: fix efi_random_alloc() to allocate memory at alloc_min or higher address
      ab8de2db
    • Linus Torvalds's avatar
      Merge tag 'x86-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 5e74df2f
      Linus Torvalds authored 
      Pull x86 fixes from Thomas Gleixner:

 - Ensure that the encryption mask at boot is properly propagated on
   5-level page tables, otherwise the PGD entry is incorrectly set to
   non-encrypted, which causes system crashes during boot.

 - Undo the deferred 5-level page table setup as it cannot work with
   memory encryption enabled.

 - Prevent inconsistent XFD state on CPU hotplug, where the MSR is reset
   to the default value but the cached variable is not, so subsequent
   comparisons might yield the wrong result and as a consequence the
   result prevents updating the MSR.

 - Register the local APIC address only once in the MPPARSE enumeration
   to prevent triggering the related WARN_ONs() in the APIC and topology
   code.

 - Handle the case where no APIC is found gracefully by registering a
   fake APIC in the topology code. That makes all related topology
   functions work correctly and does not affect the actual APIC driver
   code at all.

 - Don't evaluate logical IDs during early boot as the local APIC IDs
   are not yet enumerated and the invoked function returns an error
   code. Nothing requires the logical IDs before the final CPUID
   enumeration takes place, which happens after the enumeration.

 - Cure the fallout of the per CPU rework on UP which misplaced the
   copying of boot_cpu_data to per CPU data so that the final update to
   boot_cpu_data got lost which caused inconsistent state and boot
   crashes.

 - Use copy_from_kernel_nofault() in the kprobes setup as there is no
   guarantee that the address can be safely accessed.

 - Reorder struct members in struct saved_context to work around another
   kmemleak false positive

 - Remove the buggy code which tries to update the E820 kexec table for
   setup_data as that is never passed to the kexec kernel.

 - Update the resource control documentation to use the proper units.

 - Fix a Kconfig warning observed with tinyconfig

* tag 'x86-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/boot/64: Move 5-level paging global variable assignments back
  x86/boot/64: Apply encryption mask to 5-level pagetable update
  x86/cpu: Add model number for another Intel Arrow Lake mobile processor
  x86/fpu: Keep xfd_state in sync with MSR_IA32_XFD
  Documentation/x86: Document that resctrl bandwidth control units are MiB
  x86/mpparse: Register APIC address only once
  x86/topology: Handle the !APIC case gracefully
  x86/topology: Don't evaluate logical IDs during early boot
  x86/cpu: Ensure that CPU info updates are propagated on UP
  kprobes/x86: Use copy_from_kernel_nofault() to read from unsafe address
  x86/pm: Work around false positive kmemleak report in msr_build_context()
  x86/kexec: Do not update E820 kexec table for setup_data
  x86/config: Fix warning for 'make ARCH=x86_64 tinyconfig'
      5e74df2f
    • Linus Torvalds's avatar
      Merge tag 'sched-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · b136f68e
      Linus Torvalds authored 
      Pull scheduler doc clarification from Thomas Gleixner:
 "A single update for the documentation of the base_slice_ns tunable to
  clarify that any value which is less than the tick slice has no effect
  because the scheduler tick is not guaranteed to happen within the set
  time slice"

* tag 'sched-urgent-2024-03-24' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/doc: Update documentation for base_slice_ns and CONFIG_HZ relation
      b136f68e
    • Linus Torvalds's avatar
      Merge tag 'dma-mapping-6.9-2024-03-24' of git://git.infradead.org/users/hch/dma-mapping · 864ad046
      Linus Torvalds authored 
      Pull dma-mapping fixes from Christoph Hellwig:
 "This has a set of swiotlb alignment fixes for sometimes very long
  standing bugs from Will. We've been discussion them for a while and
  they should be solid now"

* tag 'dma-mapping-6.9-2024-03-24' of git://git.infradead.org/users/hch/dma-mapping:
  swiotlb: Reinstate page-alignment for mappings >= PAGE_SIZE
  iommu/dma: Force swiotlb_max_mapping_size on an untrusted device
  swiotlb: Fix alignment checks when both allocation and DMA masks are present
  swiotlb: Honour dma_alloc_coherent() alignment in swiotlb_alloc()
  swiotlb: Enforce page alignment in swiotlb_alloc()
  swiotlb: Fix double-allocation of slots due to broken alignment handling
      864ad046
    • Oleksandr Tymoshenko's avatar
      efi: fix panic in kdump kernel · 62b71cd7
      Oleksandr Tymoshenko authored 
      Check if get_next_variable() is actually valid pointer before
calling it. In kdump kernel this method is set to NULL that causes
panic during the kexec-ed kernel boot.

Tested with QEMU and OVMF firmware.

Fixes: bad267f9 ("efi: verify that variable services are supported")
Signed-off-by: default avatarOleksandr Tymoshenko <ovt@google.com>
Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
      62b71cd7
    • Ard Biesheuvel's avatar
      x86/efistub: Don't clear BSS twice in mixed mode · df7ecce8
      Ard Biesheuvel authored 
      Clearing BSS should only be done once, at the very beginning.
efi_pe_entry() is the entrypoint from the firmware, which may not clear
BSS and so it is done explicitly. However, efi_pe_entry() is also used
as an entrypoint by the mixed mode startup code, in which case BSS will
already have been cleared, and doing it again at this point will corrupt
global variables holding the firmware's GDT/IDT and segment selectors.

So make the memset() conditional on whether the EFI stub is running in
native mode.

Fixes: b3810c5a ("x86/efistub: Clear decompressor BSS in native EFI entrypoint")
Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
      df7ecce8
    • Ard Biesheuvel's avatar
      x86/efistub: Call mixed mode boot services on the firmware's stack · cefcd4fe
      Ard Biesheuvel authored 
      Normally, the EFI stub calls into the EFI boot services using the stack
that was live when the stub was entered. According to the UEFI spec,
this stack needs to be at least 128k in size - this might seem large but
all asynchronous processing and event handling in EFI runs from the same
stack and so quite a lot of space may be used in practice.

In mixed mode, the situation is a bit different: the bootloader calls
the 32-bit EFI stub entry point, which calls the decompressor's 32-bit
entry point, where the boot stack is set up, using a fixed allocation
of 16k. This stack is still in use when the EFI stub is started in
64-bit mode, and so all calls back into the EFI firmware will be using
the decompressor's limited boot stack.

Due to the placement of the boot stack right after the boot heap, any
stack overruns have gone unnoticed. However, commit

  5c4feadb0011983b ("x86/decompressor: Move global symbol references to C code")

moved the definition of the boot heap into C code, and now the boot
stack is placed right at the base of BSS, where any overruns will
corrupt the end of the .data section.

While it would be possible to work around this by increasing the size of
the boot stack, doing so would affect all x86 systems, and mixed mode
systems are a tiny (and shrinking) fraction of the x86 installed base.

So instead, record the firmware stack pointer value when entering from
the 32-bit firmware, and switch to this stack every time a EFI boot
service call is made.

Cc: <stable@kernel.org> # v6.1+
Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
      cefcd4fe
    • Tom Lendacky's avatar
      x86/boot/64: Move 5-level paging global variable assignments back · 9843231c
      Tom Lendacky authored 
      Commit 63bed966 ("x86/startup_64: Defer assignment of 5-level paging
global variables") moved assignment of 5-level global variables to later
in the boot in order to avoid having to use RIP relative addressing in
order to set them. However, when running with 5-level paging and SME
active (mem_encrypt=on), the variables are needed as part of the page
table setup needed to encrypt the kernel (using pgd_none(), p4d_offset(),
etc.). Since the variables haven't been set, the page table manipulation
is done as if 4-level paging is active, causing the system to crash on
boot.

While only a subset of the assignments that were moved need to be set
early, move all of the assignments back into check_la57_support() so that
these assignments aren't spread between two locations. Instead of just
reverting the fix, this uses the new RIP_REL_REF() macro when assigning
the variables.

Fixes: 63bed966 ("x86/startup_64: Defer assignment of 5-level paging global variables")
Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarArd Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/2ca419f4d0de719926fd82353f6751f717590a86.1711122067.git.thomas.lendacky@amd.com
      9843231c
    • Tom Lendacky's avatar
      x86/boot/64: Apply encryption mask to 5-level pagetable update · 4d0d7e78
      Tom Lendacky authored 
      When running with 5-level page tables, the kernel mapping PGD entry is
updated to point to the P4D table. The assignment uses _PAGE_TABLE_NOENC,
which, when SME is active (mem_encrypt=on), results in a page table
entry without the encryption mask set, causing the system to crash on
boot.

Change the assignment to use _PAGE_TABLE instead of _PAGE_TABLE_NOENC so
that the encryption mask is set for the PGD entry.

Fixes: 533568e0 ("x86/boot/64: Use RIP_REL_REF() to access early_top_pgt[]")
Signed-off-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarArd Biesheuvel <ardb@kernel.org>
Link: https://lore.kernel.org/r/8f20345cda7dbba2cf748b286e1bc00816fe649a.1711122067.git.thomas.lendacky@amd.com
      4d0d7e78
    • Tony Luck's avatar
      x86/cpu: Add model number for another Intel Arrow Lake mobile processor · 8a8a9c90
      Tony Luck authored 
      This one is the regular laptop CPU.
Signed-off-by: default avatarTony Luck <tony.luck@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240322161725.195614-1-tony.luck@intel.com
      8a8a9c90
    • Adamos Ttofari's avatar
      x86/fpu: Keep xfd_state in sync with MSR_IA32_XFD · 10e4b516
      Adamos Ttofari authored 
      Commit 67236547 ("x86/fpu: Update XFD state where required") and
commit 8bf26758 ("x86/fpu: Add XFD state to fpstate") introduced a
per CPU variable xfd_state to keep the MSR_IA32_XFD value cached, in
order to avoid unnecessary writes to the MSR.

On CPU hotplug MSR_IA32_XFD is reset to the init_fpstate.xfd, which
wipes out any stale state. But the per CPU cached xfd value is not
reset, which brings them out of sync.

As a consequence a subsequent xfd_update_state() might fail to update
the MSR which in turn can result in XRSTOR raising a #NM in kernel
space, which crashes the kernel.

To fix this, introduce xfd_set_state() to write xfd_state together
with MSR_IA32_XFD, and use it in all places that set MSR_IA32_XFD.

Fixes: 67236547 ("x86/fpu: Update XFD state where required")
Signed-off-by: default avatarAdamos Ttofari <attofari@amazon.de>
Signed-off-by: default avatarChang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
Reviewed-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240322230439.456571-1-chang.seok.bae@intel.com

Closes: https://lore.kernel.org/lkml/20230511152818.13839-1-attofari@amazon.de
      10e4b516
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7