From: Masami Hiramatsu <mhiramat@kernel.org> To: Steven Rostedt <rostedt@goodmis.org> Cc: "Naveen N . Rao" <naveen.n.rao@linux.vnet.ibm.com>, Ananth N Mavinakayanahalli <ananth@linux.ibm.com>, Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org, mhiramat@kernel.org, Sven Schnelle <svens@linux.ibm.com>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Russell King <linux@armlinux.org.uk>, Nathan Chancellor <nathan@kernel.org>, Nick Desaulniers <ndesaulniers@google.com>, linux-arm-kernel@lists.infradead.org Subject: [PATCH 04/10] arm64: kprobes: Record frame pointer with kretprobe instance Date: Fri, 15 Oct 2021 21:51:19 +0900 [thread overview] Message-ID: <163430227946.459050.807047989088672925.stgit@devnote2> (raw) In-Reply-To: <163430224341.459050.2369208860773018092.stgit@devnote2> Record the frame pointer instead of stack address with kretprobe instance as the identifier on the instance list. Since arm64 always enable CONFIG_FRAME_POINTER, we can use the actual frame pointer (x29). This will allow the stacktrace code to find the original return address from the FP alone. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> --- Changes in v2: - Update changelog according to Mark's comment. --- arch/arm64/kernel/probes/kprobes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index e7ad6da980e8..d9dfa82c1f18 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -401,14 +401,14 @@ int __init arch_populate_kprobe_blacklist(void) void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) { - return (void *)kretprobe_trampoline_handler(regs, (void *)kernel_stack_pointer(regs)); + return (void *)kretprobe_trampoline_handler(regs, (void *)regs->regs[29]); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *)regs->regs[30]; - ri->fp = (void *)kernel_stack_pointer(regs); + ri->fp = (void *)regs->regs[29]; /* replace return addr (x30) with trampoline */ regs->regs[30] = (long)&__kretprobe_trampoline;
WARNING: multiple messages have this Message-ID (diff)
From: Masami Hiramatsu <mhiramat@kernel.org> To: Steven Rostedt <rostedt@goodmis.org> Cc: "Naveen N . Rao" <naveen.n.rao@linux.vnet.ibm.com>, Ananth N Mavinakayanahalli <ananth@linux.ibm.com>, Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org, mhiramat@kernel.org, Sven Schnelle <svens@linux.ibm.com>, Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will@kernel.org>, Russell King <linux@armlinux.org.uk>, Nathan Chancellor <nathan@kernel.org>, Nick Desaulniers <ndesaulniers@google.com>, linux-arm-kernel@lists.infradead.org Subject: [PATCH 04/10] arm64: kprobes: Record frame pointer with kretprobe instance Date: Fri, 15 Oct 2021 21:51:19 +0900 [thread overview] Message-ID: <163430227946.459050.807047989088672925.stgit@devnote2> (raw) In-Reply-To: <163430224341.459050.2369208860773018092.stgit@devnote2> Record the frame pointer instead of stack address with kretprobe instance as the identifier on the instance list. Since arm64 always enable CONFIG_FRAME_POINTER, we can use the actual frame pointer (x29). This will allow the stacktrace code to find the original return address from the FP alone. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Will Deacon <will@kernel.org> Acked-by: Mark Rutland <mark.rutland@arm.com> --- Changes in v2: - Update changelog according to Mark's comment. --- arch/arm64/kernel/probes/kprobes.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/probes/kprobes.c b/arch/arm64/kernel/probes/kprobes.c index e7ad6da980e8..d9dfa82c1f18 100644 --- a/arch/arm64/kernel/probes/kprobes.c +++ b/arch/arm64/kernel/probes/kprobes.c @@ -401,14 +401,14 @@ int __init arch_populate_kprobe_blacklist(void) void __kprobes __used *trampoline_probe_handler(struct pt_regs *regs) { - return (void *)kretprobe_trampoline_handler(regs, (void *)kernel_stack_pointer(regs)); + return (void *)kretprobe_trampoline_handler(regs, (void *)regs->regs[29]); } void __kprobes arch_prepare_kretprobe(struct kretprobe_instance *ri, struct pt_regs *regs) { ri->ret_addr = (kprobe_opcode_t *)regs->regs[30]; - ri->fp = (void *)kernel_stack_pointer(regs); + ri->fp = (void *)regs->regs[29]; /* replace return addr (x30) with trampoline */ regs->regs[30] = (long)&__kretprobe_trampoline; _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
next prev parent reply other threads:[~2021-10-15 12:51 UTC|newest] Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-10-15 12:50 [PATCH 00/10] kprobes: Make KUnit and add stacktrace on kretprobe tests Masami Hiramatsu 2021-10-15 12:50 ` Masami Hiramatsu 2021-10-15 12:50 ` [PATCH 01/10] kprobes: convert tests to kunit Masami Hiramatsu 2021-10-15 12:50 ` Masami Hiramatsu 2021-10-15 12:51 ` [PATCH 02/10] kprobes: Add a test case for stacktrace from kretprobe handler Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu 2021-10-15 12:51 ` [PATCH 03/10] x86/unwind: Compile kretprobe fixup code only if CONFIG_KRETPROBES=y Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu 2021-10-15 13:10 ` Masami Hiramatsu 2021-10-15 13:10 ` Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu [this message] 2021-10-15 12:51 ` [PATCH 04/10] arm64: kprobes: Record frame pointer with kretprobe instance Masami Hiramatsu 2021-10-15 12:51 ` [PATCH 05/10] arm64: kprobes: Make a frame pointer on __kretprobe_trampoline Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu 2021-10-15 12:51 ` [PATCH 06/10] arm64: Recover kretprobe modified return address in stacktrace Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu 2021-10-15 12:51 ` [PATCH 07/10] ARM: clang: Do not rely on lr register for stacktrace Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu 2021-10-15 12:51 ` [PATCH 08/10] ARM: kprobes: Make a frame pointer on __kretprobe_trampoline Masami Hiramatsu 2021-10-15 12:51 ` Masami Hiramatsu 2021-10-16 10:37 ` kernel test robot 2021-10-16 10:37 ` kernel test robot 2021-10-16 21:15 ` Russell King (Oracle) 2021-10-16 21:15 ` Russell King (Oracle) 2021-10-18 5:55 ` Masami Hiramatsu 2021-10-18 5:55 ` Masami Hiramatsu 2021-10-15 12:52 ` [PATCH 09/10] ARM: Recover kretprobe modified return address in stacktrace Masami Hiramatsu 2021-10-15 12:52 ` Masami Hiramatsu 2021-10-15 12:52 ` [PATCH 10/10] [RFC] arm64: kprobes: Detect error of kretprobe return address fixup Masami Hiramatsu 2021-10-15 12:52 ` Masami Hiramatsu
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=163430227946.459050.807047989088672925.stgit@devnote2 \ --to=mhiramat@kernel.org \ --cc=ananth@linux.ibm.com \ --cc=catalin.marinas@arm.com \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linux@armlinux.org.uk \ --cc=mingo@kernel.org \ --cc=nathan@kernel.org \ --cc=naveen.n.rao@linux.vnet.ibm.com \ --cc=ndesaulniers@google.com \ --cc=rostedt@goodmis.org \ --cc=svens@linux.ibm.com \ --cc=will@kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.