moonjuice/kernel_arpi
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Merge tag 'objtool-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Browse Source 
Pull objtool fix from Thomas Gleixner:
 "A single objtool fix to handle the PUSHF/POPF validation correctly for
  the paravirt changes which modified arch_local_irq_restore not to use
  popf"

* tag 'objtool-urgent-2021-03-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool,x86: Fix uaccess PUSHF/POPF validation
This commit is contained in:
Linus Torvalds
2021-03-14 13:15:55 -07:00
parent fa509ff879 ba08abca66
commit 19469d2ada
2 changed files with 7 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/include/asm/smap.h
View File

@@ -58,9 +58,8 @@ static __always_inline unsigned long smap_save(void)
unsigned long flags;
asm volatile ("# smap_save\n\t"
ALTERNATIVE("jmp 1f", "", X86_FEATURE_SMAP)
"pushf; pop %0; " __ASM_CLAC "\n\t"
"1:"
ALTERNATIVE("", "pushf; pop %0; " __ASM_CLAC "\n\t",
X86_FEATURE_SMAP)
: "=rm" (flags) : : "memory", "cc");
return flags;
@@ -69,9 +68,8 @@ static __always_inline unsigned long smap_save(void)
static __always_inline void smap_restore(unsigned long flags)
{
asm volatile ("# smap_restore\n\t"
ALTERNATIVE("jmp 1f", "", X86_FEATURE_SMAP)
"push %0; popf\n\t"
"1:"
ALTERNATIVE("", "push %0; popf\n\t",
X86_FEATURE_SMAP)
: : "g" (flags) : "memory", "cc");
}

3
tools/objtool/check.c
View File

@@ -2442,6 +2442,9 @@ static int handle_insn_ops(struct instruction *insn, struct insn_state *state)
if (update_cfi_state(insn, &state->cfi, op))
return 1;
if (!insn->alt_group)
continue;
if (op->dest.type == OP_DEST_PUSHF) {
if (!state->uaccess_stack) {
state->uaccess_stack = 1;