summaryrefslogtreecommitdiff
path: root/arch/x86/kernel/kprobes
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2023-02-21 04:29:55 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2023-02-21 04:29:55 +0300
commita2f0e7eee1344eb9f91b22bc72d9eb0a52b849c9 (patch)
treecba6f8b16f26c986e66b291416103c859697b6b0 /arch/x86/kernel/kprobes
parent6e649d08568220ee88deef0a1ad8b3a935420cf2 (diff)
parentc828441f21ddc819a28b5723a72e3c840e9de1c6 (diff)
downloadlinux-a2f0e7eee1344eb9f91b22bc72d9eb0a52b849c9.tar.xz
Merge tag 'perf-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar: - Optimize perf_sample_data layout - Prepare sample data handling for BPF integration - Update the x86 PMU driver for Intel Meteor Lake - Restructure the x86 uncore code to fix a SPR (Sapphire Rapids) discovery breakage - Fix the x86 Zhaoxin PMU driver - Cleanups * tag 'perf-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits) perf/x86/intel/uncore: Add Meteor Lake support x86/perf/zhaoxin: Add stepping check for ZXC perf/x86/intel/ds: Fix the conversion from TSC to perf time perf/x86/uncore: Don't WARN_ON_ONCE() for a broken discovery table perf/x86/uncore: Add a quirk for UPI on SPR perf/x86/uncore: Ignore broken units in discovery table perf/x86/uncore: Fix potential NULL pointer in uncore_get_alias_name perf/x86/uncore: Factor out uncore_device_to_die() perf/core: Call perf_prepare_sample() before running BPF perf/core: Introduce perf_prepare_header() perf/core: Do not pass header for sample ID init perf/core: Set data->sample_flags in perf_prepare_sample() perf/core: Add perf_sample_save_brstack() helper perf/core: Add perf_sample_save_raw_data() helper perf/core: Add perf_sample_save_callchain() helper perf/core: Save the dynamic parts of sample data size x86/kprobes: Use switch-case for 0xFF opcodes in prepare_emulation perf/core: Change the layout of perf_sample_data perf/x86/msr: Add Meteor Lake support perf/x86/cstate: Add Meteor Lake support ...
Diffstat (limited to 'arch/x86/kernel/kprobes')
-rw-r--r--arch/x86/kernel/kprobes/core.c34
1 files changed, 11 insertions, 23 deletions
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 695873c0f50b..754da3b226f9 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -659,17 +659,19 @@ static int prepare_emulation(struct kprobe *p, struct insn *insn)
* is determined by the MOD/RM byte.
*/
opcode = insn->modrm.bytes[0];
- if ((opcode & 0x30) == 0x10) {
- if ((opcode & 0x8) == 0x8)
- return -EOPNOTSUPP; /* far call */
- /* call absolute, indirect */
+ switch (X86_MODRM_REG(opcode)) {
+ case 0b010: /* FF /2, call near, absolute indirect */
p->ainsn.emulate_op = kprobe_emulate_call_indirect;
- } else if ((opcode & 0x30) == 0x20) {
- if ((opcode & 0x8) == 0x8)
- return -EOPNOTSUPP; /* far jmp */
- /* jmp near absolute indirect */
+ break;
+ case 0b100: /* FF /4, jmp near, absolute indirect */
p->ainsn.emulate_op = kprobe_emulate_jmp_indirect;
- } else
+ break;
+ case 0b011: /* FF /3, call far, absolute indirect */
+ case 0b101: /* FF /5, jmp far, absolute indirect */
+ return -EOPNOTSUPP;
+ }
+
+ if (!p->ainsn.emulate_op)
break;
if (insn->addr_bytes != sizeof(unsigned long))
@@ -990,20 +992,6 @@ int kprobe_int3_handler(struct pt_regs *regs)
kprobe_post_process(p, regs, kcb);
return 1;
}
- }
-
- if (*addr != INT3_INSN_OPCODE) {
- /*
- * The breakpoint instruction was removed right
- * after we hit it. Another cpu has removed
- * either a probepoint or a debugger breakpoint
- * at this address. In either case, no further
- * handling of this interrupt is appropriate.
- * Back up over the (now missing) int3 and run
- * the original instruction.
- */
- regs->ip = (unsigned long)addr;
- return 1;
} /* else: not a kprobe fault; let the kernel handle it */
return 0;