linux-kernel - [PATCH] clear IOCK NMI before panic

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Date:	Fri, 15 Feb 2013 10:52:27 +0900
From:	Naohiro Ooiwa <naohiro.ooiwa@...aclelinux.com>
To:	linux-kernel@...r.kernel.org
CC:	Kurt Garloff <garloff@...e.de>,
	Roberto Angelino <robertangelino@...il.com>,
	Greg Kroah-Hartman <gregkh@...e.de>, mingo@...nel.org
Subject: [PATCH] clear IOCK NMI before panic

Hi all

I tried to push an NMI button on HP DL380p Gen8's iLO4.
and then I received an IOCK NMI error.
When panic_on_io_nmi is set to 0, it seems that IOCK NMI error is sent repeatedly.

In case of panic_on_io_nmi=1 and kdump is available,
the second kernel started. But IOCK NMI is sent repeatedly
and second kernel couldn't take a dump.

Though this is just my guess,
We should clear the IOCK of NMI reason before panic().

I tried to create a patch, which works for me.
Is my patch reasonable?


Thanks you.
Naohiro Ooiwa


Signed-off-by: Naohiro Ooiwa <naohiro.ooiwa@...aclelinux.com>
---
 arch/x86/kernel/nmi.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/nmi.c b/arch/x86/kernel/nmi.c
index f84f5c5..c3cbfbe 100644
--- a/arch/x86/kernel/nmi.c
+++ b/arch/x86/kernel/nmi.c
@@ -209,8 +209,11 @@ io_check_error(unsigned char reason, struct pt_regs *regs)
 		 reason, smp_processor_id());
 	show_regs(regs);

-	if (panic_on_io_nmi)
+	if (panic_on_io_nmi) {
+		reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_IOCHK;
+		outb(reason, NMI_REASON_PORT);
 		panic("NMI IOCK error: Not continuing");
+	}

 	/* Re-enable the IOCK line, wait for a few seconds */
 	reason = (reason & NMI_REASON_CLEAR_MASK) | NMI_REASON_CLEAR_IOCHK;
-- 
1.7.10.4





--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/