From: Josh Poimboeuf <jpoimboe@redhat.com>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org,
Peter Zijlstra <peterz@infradead.org>,
Vince Weaver <vincent.weaver@maine.edu>, Dave Jones <dsj@fb.com>,
Jann Horn <jannh@google.com>, Miroslav Benes <mbenes@suse.cz>,
Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH v2 09/11] x86/unwind/orc: Prevent unwinding before ORC initialization
Date: Sat, 25 Apr 2020 05:12:47 -0500 [thread overview]
Message-ID: <20200425101247.l2xpp23vmmv7zfuv@treble> (raw)
In-Reply-To: <069d1499ad606d85532eb32ce39b2441679667d5.1587808742.git.jpoimboe@redhat.com>
On Sat, Apr 25, 2020 at 05:03:08AM -0500, Josh Poimboeuf wrote:
> If the unwinder is called before the ORC data has been initialized,
> orc_find() returns NULL, and it tries to fall back to using frame
> pointers. This can cause some unexpected warnings during boot.
>
> Move the 'orc_init' check from orc_find() to __unwind_init(), so that it
> doesn't even try to unwind from an uninitialized state.
>
> Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder")
> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
> Reviewed-by: Miroslav Benes <mbenes@suse.cz>
I got a weird error when sending this one:
4.7.1 Error: too much mail from 10.10.114.29
If anybody didn't get it, let me know and I can bounce it.
> ---
> arch/x86/kernel/unwind_orc.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/arch/x86/kernel/unwind_orc.c b/arch/x86/kernel/unwind_orc.c
> index e9f5a20c69c6..cb11567361cc 100644
> --- a/arch/x86/kernel/unwind_orc.c
> +++ b/arch/x86/kernel/unwind_orc.c
> @@ -148,9 +148,6 @@ static struct orc_entry *orc_find(unsigned long ip)
> {
> static struct orc_entry *orc;
>
> - if (!orc_init)
> - return NULL;
> -
> if (ip == 0)
> return &null_orc_entry;
>
> @@ -591,6 +588,9 @@ EXPORT_SYMBOL_GPL(unwind_next_frame);
> void __unwind_start(struct unwind_state *state, struct task_struct *task,
> struct pt_regs *regs, unsigned long *first_frame)
> {
> + if (!orc_init)
> + goto done;
> +
> memset(state, 0, sizeof(*state));
> state->task = task;
>
> --
> 2.21.1
>
--
Josh
next prev parent reply other threads:[~2020-04-25 10:13 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-04-25 10:02 [PATCH v2 00/11] ORC fixes Josh Poimboeuf
2020-04-25 10:03 ` [PATCH v2 01/11] objtool: Fix stack offset tracking for indirect CFAs Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:03 ` [PATCH v2 02/11] x86/entry/64: Fix unwind hints in register clearing code Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:03 ` [PATCH v2 03/11] x86/entry/64: Fix unwind hints in kernel exit path Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:03 ` [PATCH v2 04/11] x86/entry/64: Fix unwind hints in __switch_to_asm() Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:03 ` [PATCH v2 05/11] x86/entry/64: Fix unwind hints in rewind_stack_do_exit() Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Jann Horn
2020-04-25 10:03 ` [PATCH v2 06/11] x86/unwind/orc: Convert global variables to static Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2024-02-28 23:35 ` [PATCH v2 06/11] " Steven Rostedt
2024-02-29 0:03 ` Josh Poimboeuf
2024-02-29 0:14 ` Steven Rostedt
2024-02-29 0:42 ` Josh Poimboeuf
2024-02-29 23:40 ` Steven Rostedt
2024-03-18 15:58 ` Steven Rostedt
2020-04-25 10:03 ` [PATCH v2 07/11] x86/unwind: Prevent false warnings for non-current tasks Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:03 ` [PATCH v2 08/11] x86/unwind/orc: Don't skip the first frame for inactive tasks Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Miroslav Benes
2020-04-25 10:03 ` [PATCH v2 09/11] x86/unwind/orc: Prevent unwinding before ORC initialization Josh Poimboeuf
2020-04-25 10:12 ` Josh Poimboeuf [this message]
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:06 ` [PATCH v2 10/11] x86/unwind/orc: Fix error path for bad ORC entry type Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:06 ` [PATCH v2 11/11] x86/unwind/orc: Fix premature unwind stoppage due to IRET frames Josh Poimboeuf
2020-04-26 6:47 ` [tip: x86/urgent] " tip-bot2 for Josh Poimboeuf
2020-04-25 10:25 ` [PATCH v2 00/11] ORC fixes Ingo Molnar
2020-04-25 10:41 ` Josh Poimboeuf
2020-04-26 7:26 ` Ingo Molnar
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