Now that UPROBE_FIX_IP/UPROBE_FIX_CALL are mutually exclusive we can use a single "fix_ip_or_call" enum instead of 2 fix_* booleans. This way the logic looks more understandable and clean to me.
While at it, join "case 0xea" with other "ip is correct" ret/lret cases. Also change default_post_xol_op() to use "else if" for the same reason. Signed-off-by: Oleg Nesterov <[email protected]> --- arch/x86/kernel/uprobes.c | 27 +++++++++++---------------- 1 files changed, 11 insertions(+), 16 deletions(-) diff --git a/arch/x86/kernel/uprobes.c b/arch/x86/kernel/uprobes.c index 4c60b7a..4ae2406 100644 --- a/arch/x86/kernel/uprobes.c +++ b/arch/x86/kernel/uprobes.c @@ -424,10 +424,9 @@ static int default_post_xol_op(struct arch_uprobe *auprobe, struct pt_regs *regs long correction = (long)(utask->vaddr - utask->xol_vaddr); handle_riprel_post_xol(auprobe, regs, &correction); - if (auprobe->def.fixups & UPROBE_FIX_IP) + if (auprobe->def.fixups & UPROBE_FIX_IP) { regs->ip += correction; - - if (auprobe->def.fixups & UPROBE_FIX_CALL) { + } else if (auprobe->def.fixups & UPROBE_FIX_CALL) { regs->sp += sizeof_long(); if (push_ret_address(regs, utask->vaddr + auprobe->def.ilen)) return -ERESTART; @@ -612,7 +611,7 @@ static int branch_setup_xol_ops(struct arch_uprobe *auprobe, struct insn *insn) int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long addr) { struct insn insn; - bool fix_ip = true, fix_call = false; + u8 fix_ip_or_call = UPROBE_FIX_IP; int ret; ret = uprobe_init_insn(auprobe, &insn, is_64bit_mm(mm)); @@ -636,21 +635,20 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, case 0xcb: case 0xc2: case 0xca: - fix_ip = false; + case 0xea: /* jmp absolute -- ip is correct */ + fix_ip_or_call = 0; break; case 0x9a: /* call absolute - Fix return addr, not ip */ - fix_call = true; - fix_ip = false; - break; - case 0xea: /* jmp absolute -- ip is correct */ - fix_ip = false; + fix_ip_or_call = UPROBE_FIX_CALL; break; case 0xff: switch (MODRM_REG(&insn)) { case 2: case 3: /* call or lcall, indirect */ - fix_call = true; + fix_ip_or_call = UPROBE_FIX_CALL; + break; case 4: case 5: /* jmp or ljmp, indirect */ - fix_ip = false; + fix_ip_or_call = 0; + break; } /* fall through */ default: @@ -658,10 +656,7 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, } auprobe->def.ilen = insn.length; - if (fix_ip) - auprobe->def.fixups |= UPROBE_FIX_IP; - if (fix_call) - auprobe->def.fixups |= UPROBE_FIX_CALL; + auprobe->def.fixups |= fix_ip_or_call; auprobe->ops = &default_xol_ops; return 0; -- 1.5.5.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
