From: Christophe LEROY <christophe.leroy@c-s.fr>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>,
Paul Mackerras <paulus@samba.org>,
Michael Ellerman <mpe@ellerman.id.au>,
npiggin@gmail.com
Cc: linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
"stable@vger.kernel.org" <stable@vger.kernel.org>
Subject: Re: [PATCH] powerpc/traps: restore recoverability of machine_check interrupts
Date: Mon, 15 Oct 2018 09:40:50 +0200 [thread overview]
Message-ID: <ab520cc1-11b7-ddc6-2393-8f1315db4db3@c-s.fr> (raw)
In-Reply-To: <f79824d5da910441ede885fa32a25083c4cc9359.1539422122.git.christophe.leroy@c-s.fr>
Cc: stable@vger.kernel.org <stable@vger.kernel.org>
Le 13/10/2018 à 11:16, Christophe Leroy a écrit :
> commit b96672dd840f ("powerpc: Machine check interrupt is a non-
> maskable interrupt") added a call to nmi_enter() at the beginning of
> machine check restart exception handler. Due to that, in_interrupt()
> always returns true regardless of the state before entering the
> exception, and die() panics even when the system was not already in
> interrupt.
>
> This patch calls nmi_exit() before calling die() in order to restore
> the interrupt state we had before calling nmi_enter()
>
> Fixes: b96672dd840f ("powerpc: Machine check interrupt is a non-maskable interrupt")
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> ---
> arch/powerpc/kernel/traps.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
> index fd58749b4d6b..4f880c2a6e4c 100644
> --- a/arch/powerpc/kernel/traps.c
> +++ b/arch/powerpc/kernel/traps.c
> @@ -765,12 +765,17 @@ void machine_check_exception(struct pt_regs *regs)
> if (check_io_access(regs))
> goto bail;
>
> - die("Machine check", regs, SIGBUS);
> -
> /* Must die if the interrupt is not recoverable */
> if (!(regs->msr & MSR_RI))
> nmi_panic(regs, "Unrecoverable Machine check");
>
> + if (!nested)
> + nmi_exit();
> +
> + die("Machine check", regs, SIGBUS);
> +
> + return;
> +
> bail:
> if (!nested)
> nmi_exit();
>
next prev parent reply other threads:[~2018-10-15 7:42 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-10-13 9:16 [PATCH] powerpc/traps: restore recoverability of machine_check interrupts Christophe Leroy
2018-10-15 7:40 ` Christophe LEROY [this message]
2018-10-16 1:10 ` Nicholas Piggin
2018-10-22 9:37 ` Michael Ellerman
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=ab520cc1-11b7-ddc6-2393-8f1315db4db3@c-s.fr \
--to=christophe.leroy@c-s.fr \
--cc=benh@kernel.crashing.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linuxppc-dev@lists.ozlabs.org \
--cc=mpe@ellerman.id.au \
--cc=npiggin@gmail.com \
--cc=paulus@samba.org \
--cc=stable@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).