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| author |  Linus Torvalds <torvalds@linux-foundation.org>
| 2024-01-08 17:48:35 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org>
| 2024-01-08 17:48:35 -0800 |
| commit | 2fdbcf715a1b9dd1468317f7cd4b4cd327a09781 (patch) | |
| tree | e0ad0ad6937fb6c243aac5c8818ed6fd0d902a15 /arch/x86/entry/calling.h | |
| parent | Merge tag 'x86-core-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/... (diff) | |
| parent | x86/entry: Harden return-to-user (diff) | |
| download | linux-2fdbcf715a1b9dd1468317f7cd4b4cd327a09781.tar.gz linux-2fdbcf715a1b9dd1468317f7cd4b4cd327a09781.tar.bz2 linux-2fdbcf715a1b9dd1468317f7cd4b4cd327a09781.zip | |
Merge tag 'x86-entry-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 entry updates from Ingo Molnar:
- Optimize common_interrupt_return()
- Harden the return-to-user code by making a CONFIG_DEBUG_ENTRY=y check
unconditional & moving it closer to the IRET.
* tag 'x86-entry-2024-01-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/entry: Harden return-to-user
x86/entry: Optimize common_interrupt_return()
Diffstat (limited to 'arch/x86/entry/calling.h')
| -rw-r--r-- | arch/x86/entry/calling.h | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/entry/calling.h b/arch/x86/entry/calling.h index f6907627172b..9f1d94790a54 100644 --- a/arch/x86/entry/calling.h +++ b/arch/x86/entry/calling.h @@ -175,8 +175,7 @@ For 32-bit we have the following conventions - kernel is built with #define THIS_CPU_user_pcid_flush_mask \ PER_CPU_VAR(cpu_tlbstate) + TLB_STATE_user_pcid_flush_mask -.macro SWITCH_TO_USER_CR3_NOSTACK scratch_reg:req scratch_reg2:req - ALTERNATIVE "jmp .Lend_\@", "", X86_FEATURE_PTI +.macro SWITCH_TO_USER_CR3 scratch_reg:req scratch_reg2:req mov %cr3, \scratch_reg ALTERNATIVE "jmp .Lwrcr3_\@", "", X86_FEATURE_PCID @@ -206,13 +205,20 @@ For 32-bit we have the following conventions - kernel is built with /* Flip the PGD to the user version */ orq $(PTI_USER_PGTABLE_MASK), \scratch_reg mov \scratch_reg, %cr3 +.endm + +.macro SWITCH_TO_USER_CR3_NOSTACK scratch_reg:req scratch_reg2:req + ALTERNATIVE "jmp .Lend_\@", "", X86_FEATURE_PTI + SWITCH_TO_USER_CR3 \scratch_reg \scratch_reg2 .Lend_\@: .endm .macro SWITCH_TO_USER_CR3_STACK scratch_reg:req + ALTERNATIVE "jmp .Lend_\@", "", X86_FEATURE_PTI pushq %rax - SWITCH_TO_USER_CR3_NOSTACK scratch_reg=\scratch_reg scratch_reg2=%rax + SWITCH_TO_USER_CR3 scratch_reg=\scratch_reg scratch_reg2=%rax popq %rax +.Lend_\@: .endm .macro SAVE_AND_SWITCH_TO_KERNEL_CR3 scratch_reg:req save_reg:req |