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mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-28 15:13:55 +08:00
linux-next/arch/x86/entry
Lai Jiangshan c42b145181 x86/sev: Annotate stack change in the #VC handler
In idtentry_vc(), vc_switch_off_ist() determines a safe stack to
switch to, off of the IST stack. Annotate the new stack switch with
ENCODE_FRAME_POINTER in case UNWINDER_FRAME_POINTER is used.

A stack walk before looks like this:

  CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0-rc7+ #2
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Call Trace:
   <TASK>
   dump_stack_lvl
   dump_stack
   kernel_exc_vmm_communication
   asm_exc_vmm_communication
   ? native_read_msr
   ? __x2apic_disable.part.0
   ? x2apic_setup
   ? cpu_init
   ? trap_init
   ? start_kernel
   ? x86_64_start_reservations
   ? x86_64_start_kernel
   ? secondary_startup_64_no_verify
   </TASK>

and with the fix, the stack dump is exact:

  CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0-rc7+ #3
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Call Trace:
   <TASK>
   dump_stack_lvl
   dump_stack
   kernel_exc_vmm_communication
   asm_exc_vmm_communication
  RIP: 0010:native_read_msr
  Code: ...
  < snipped regs >
   ? __x2apic_disable.part.0
   x2apic_setup
   cpu_init
   trap_init
   start_kernel
   x86_64_start_reservations
   x86_64_start_kernel
   secondary_startup_64_no_verify
   </TASK>

  [ bp: Test in a SEV-ES guest and rewrite the commit message to
    explain what exactly this does. ]

Fixes: a13644f3a5 ("x86/entry/64: Add entry code for #VC handler")
Signed-off-by: Lai Jiangshan <jiangshan.ljs@antgroup.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220316041612.71357-1-jiangshanlai@gmail.com
2022-05-18 20:36:03 +02:00
..
syscalls Kbuild updates for v5.18 2022-03-31 11:59:03 -07:00
vdso - Get rid of all the .fixup sections because this generates 2022-01-12 16:31:19 -08:00
vsyscall x86: Prepare asm files for straight-line-speculation 2021-12-08 12:25:37 +01:00
calling.h x86/entry: Split PUSH_AND_CLEAR_REGS into two submacros 2021-05-12 10:49:15 +02:00
common.c X86 entry code related updates: 2021-06-29 12:44:51 -07:00
entry_32.S Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
entry_64_compat.S x86/ibt,sev: Annotations 2022-03-15 10:32:41 +01:00
entry_64.S x86/sev: Annotate stack change in the #VC handler 2022-05-18 20:36:03 +02:00
Makefile x86/syscalls: Don't adjust CFLAGS for syscall tables 2021-05-25 16:59:23 +02:00
syscall_32.c x86/syscalls: Stop filling syscall arrays with *_sys_ni_syscall 2021-05-20 15:03:59 +02:00
syscall_64.c x86/syscalls: Stop filling syscall arrays with *_sys_ni_syscall 2021-05-20 15:03:59 +02:00
syscall_x32.c x86/syscalls: Stop filling syscall arrays with *_sys_ni_syscall 2021-05-20 15:03:59 +02:00
thunk_32.S x86: Prepare asm files for straight-line-speculation 2021-12-08 12:25:37 +01:00
thunk_64.S x86: Prepare asm files for straight-line-speculation 2021-12-08 12:25:37 +01:00