diff options
Diffstat (limited to 'arch/i386/kernel/paravirt.c')
| -rw-r--r-- | arch/i386/kernel/paravirt.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/arch/i386/kernel/paravirt.c b/arch/i386/kernel/paravirt.c index 53f07a8275e..79c167fcaee 100644 --- a/arch/i386/kernel/paravirt.c +++ b/arch/i386/kernel/paravirt.c @@ -124,20 +124,28 @@ unsigned paravirt_patch_ignore(unsigned len) return len; } +struct branch { + unsigned char opcode; + u32 delta; +} __attribute__((packed)); + unsigned paravirt_patch_call(void *target, u16 tgt_clobbers, void *site, u16 site_clobbers, unsigned len) { unsigned char *call = site; unsigned long delta = (unsigned long)target - (unsigned long)(call+5); + struct branch b; if (tgt_clobbers & ~site_clobbers) return len; /* target would clobber too much for this site */ if (len < 5) return len; /* call too long for patch site */ - *call++ = 0xe8; /* call */ - *(unsigned long *)call = delta; + b.opcode = 0xe8; /* call */ + b.delta = delta; + BUILD_BUG_ON(sizeof(b) != 5); + text_poke(call, (unsigned char *)&b, 5); return 5; } @@ -150,8 +158,9 @@ unsigned paravirt_patch_jmp(void *target, void *site, unsigned len) if (len < 5) return len; /* call too long for patch site */ - *jmp++ = 0xe9; /* jmp */ - *(unsigned long *)jmp = delta; + b.opcode = 0xe9; /* jmp */ + b.delta = delta; + text_poke(call, (unsigned char *)&b, 5); return 5; } |