linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: "Russell King (Oracle)" <linux@armlinux.org.uk>
To: Ard Biesheuvel <ardb@kernel.org>
Cc: Corentin Labbe <clabbe.montjoie@gmail.com>,
	Linus Walleij <linus.walleij@linaro.org>,
	Arnd Bergmann <arnd@arndb.de>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: boot flooded with unwind: Index not found
Date: Wed, 9 Mar 2022 01:08:17 +0000	[thread overview]
Message-ID: <Yif+AY3DShT9Z6Q+@shell.armlinux.org.uk> (raw)
In-Reply-To: <YifuVmkcb1ie7bzk@shell.armlinux.org.uk>

On Wed, Mar 09, 2022 at 12:01:26AM +0000, Russell King (Oracle) wrote:
> To reinterate what I've just put on IRC - we have not got to the bottom
> of this problem yet - it still very much exists.
> 
> There seems to be something of a fundamental issue with the unwinder,
> it now appears to be going wrong and failing to unwind beyond a
> couple of functions, and the address it's coming out with appears to
> be incorrect. I've only just discovered this because I created my very
> own bug, and yet again, the timing sucks with the proximity of the
> merge window.
> 
> I'm getting:
> 
> [   13.198803] [<c0017728>] (unwind_backtrace) from [<c0012828>] (show_stack+0x10/0x14)
> [   13.198820] [<c0012828>] (show_stack) from [<c2be78d4>] (0xc2be78d4)
> 
> for the WARN_ON() stacktrace, and that address that apparently called
> show_stack() is most definitely rubbish and incorrect. This makes any
> WARN_ON() condition undebuggable.
> 
> This is with both 9183/1 and 9184/1 applied on top of pulling your
> "arm-ftrace-for-rmk" tag and also with just the "arm-vmap-stacks-v6"
> tag. This seems to point at one of these patches breaking the
> unwinder:
> 
> a1c510d0adc6 ARM: implement support for vmap'ed stacks
> 532319b9c418 ARM: unwind: disregard unwind info before stack frame is set up

The above commit appears to be what's breaking the unwinder. Without
this I get sane stacktraces. With it, the unwinder spits out stupid
function addresses.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

  reply	other threads:[~2022-03-09  1:10 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-03-01 15:48 boot flooded with unwind: Index not found Corentin Labbe
2022-03-01 15:49 ` Russell King (Oracle)
2022-03-01 16:37   ` Ard Biesheuvel
2022-03-01 16:52     ` Ard Biesheuvel
2022-03-01 18:19       ` Corentin Labbe
2022-03-02  8:39       ` Corentin Labbe
2022-03-02  8:44         ` Ard Biesheuvel
     [not found]           ` <Yh8w7ldudhmbYv4N@Red>
2022-03-02  9:45             ` Ard Biesheuvel
2022-03-02 10:09               ` Corentin Labbe
2022-03-02 11:12                 ` Russell King (Oracle)
2022-03-02 11:19                   ` Ard Biesheuvel
2022-03-02 11:22                     ` Russell King (Oracle)
2022-03-09  0:01                       ` Russell King (Oracle)
2022-03-09  1:08                         ` Russell King (Oracle) [this message]
2022-03-09  7:20                           ` Ard Biesheuvel
2022-03-01 18:16   ` Corentin Labbe

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=Yif+AY3DShT9Z6Q+@shell.armlinux.org.uk \
    --to=linux@armlinux.org.uk \
    --cc=ardb@kernel.org \
    --cc=arnd@arndb.de \
    --cc=clabbe.montjoie@gmail.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.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: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).