linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Balbir Singh <bsingharora@gmail.com>
To: linuxppc-dev@lists.ozlabs.org
Cc: npiggin@gmail.com, mpe@ellerman.id.au,
	Balbir Singh <bsingharora@gmail.com>
Subject: [PATCH] powerpc/powernv/mce: Don't silently restart the machine
Date: Thu,  8 Mar 2018 11:36:06 +1100	[thread overview]
Message-ID: <20180308003606.10721-1-bsingharora@gmail.com> (raw)

On MCE the current code will restart the machine with
ppc_md.restart(). This case was extremely unlikely since
prior to that a skiboot call is made and that resulted in
a checkstop for analysis.

With newer skiboots, on P9 we don't checkstop the box by
default, instead we return back to the kernel to extract
useful information at the time of the MCE. While we still
get this information, this patch converts the restart to
a panic(), so that if configured a dump can be taken and
we can track and probably debug the potential issue causing
the MCE.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
---

Changelog
	- Change panic to use the passed msg, instead of a hard
	coded MCE one, since this code path is common to both
	HMI's and MCE's

 arch/powerpc/platforms/powernv/opal.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index c15182765ff5..516e23de5a3d 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -490,9 +490,12 @@ void pnv_platform_error_reboot(struct pt_regs *regs, const char *msg)
 	 *    opal to trigger checkstop explicitly for error analysis.
 	 *    The FSP PRD component would have already got notified
 	 *    about this error through other channels.
+	 * 4. We are running on a newer skiboot that by default does
+	 *    not cause a checkstop, drops us back to the kernel to
+	 *    extract context and state at the time of the error.
 	 */
 
-	ppc_md.restart(NULL);
+	panic(msg);
 }
 
 int opal_machine_check(struct pt_regs *regs)
-- 
2.13.6

             reply	other threads:[~2018-03-08  0:36 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-08  0:36 Balbir Singh [this message]
2018-03-08  1:20 ` [PATCH] powerpc/powernv/mce: Don't silently restart the machine Stewart Smith
2018-03-08  9:33   ` Balbir Singh
2018-03-14  9:28 ` 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=20180308003606.10721-1-bsingharora@gmail.com \
    --to=bsingharora@gmail.com \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mpe@ellerman.id.au \
    --cc=npiggin@gmail.com \
    /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).