android/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/text-patching: Make text_gen_insn() play nice with ANNOTATE_NOENDBR

Browse Source 
Upstream commit: bbf92368b0b1fe472d489e62d3340d7897e9c697

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.638561109@infradead.org
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Zijlstra 2022-03-08 16:30:19 +01:00 committed by Greg Kroah-Hartman
parent c13d426040
commit e752912ce1
1 changed files with 9 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/x86/include/asm/text-patching.h
View File

@ -101,13 +101,21 @@ void *text_gen_insn(u8 opcode, const void *addr, const void *dest)
static union text_poke_insn insn; /* per instance */ static union text_poke_insn insn; /* per instance */
int size = text_opcode_size(opcode); int size = text_opcode_size(opcode);
/*
* Hide the addresses to avoid the compiler folding in constants when
* referencing code, these can mess up annotations like
* ANNOTATE_NOENDBR.
*/
OPTIMIZER_HIDE_VAR(addr);
OPTIMIZER_HIDE_VAR(dest);
insn.opcode = opcode; insn.opcode = opcode;
if (size > 1) { if (size > 1) {
insn.disp = (long)dest - (long)(addr + size); insn.disp = (long)dest - (long)(addr + size);
if (size == 2) { if (size == 2) {
/* /*
* Ensure that for JMP9 the displacement * Ensure that for JMP8 the displacement
* actually fits the signed byte. * actually fits the signed byte.
*/ */
BUG_ON((insn.disp >> 31) != (insn.disp >> 7)); BUG_ON((insn.disp >> 31) != (insn.disp >> 7));