diff options
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kernel/alternative.c | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 99ef8b6f9a1a..ccd32013c47a 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -625,10 +625,23 @@ extern struct paravirt_patch_site __start_parainstructions[], * * See entry_{32,64}.S for more details. */ -static void __init int3_magic(unsigned int *ptr) -{ - *ptr = 1; -} + +/* + * We define the int3_magic() function in assembly to control the calling + * convention such that we can 'call' it from assembly. + */ + +extern void int3_magic(unsigned int *ptr); /* defined in asm */ + +asm ( +" .pushsection .init.text, \"ax\", @progbits\n" +" .type int3_magic, @function\n" +"int3_magic:\n" +" movl $1, (%" _ASM_ARG1 ")\n" +" ret\n" +" .size int3_magic, .-int3_magic\n" +" .popsection\n" +); extern __initdata unsigned long int3_selftest_ip; /* defined in asm below */ @@ -676,7 +689,9 @@ static void __init int3_selftest(void) "int3_selftest_ip:\n\t" __ASM_SEL(.long, .quad) " 1b\n\t" ".popsection\n\t" - : : __ASM_SEL_RAW(a, D) (&val) : "memory"); + : ASM_CALL_CONSTRAINT + : __ASM_SEL_RAW(a, D) (&val) + : "memory"); BUG_ON(val != 1); |