All of lore.kernel.org
 help / color / mirror / Atom feed
From: Gabriele Paoloni <gabriele.paoloni@intel.com>
To: tony.luck@intel.com, bp@alien8.de, tglx@linutronix.de,
	mingo@redhat.com, x86@kernel.org, hpa@zytor.com,
	linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: gabriele.paoloni@intel.com, linux-safety@lists.elisa.tech
Subject: [PATCH v2 1/5] x86/mce: do not overwrite no_way_out if mce_end() fails
Date: Fri, 27 Nov 2020 16:18:15 +0000	[thread overview]
Message-ID: <20201127161819.3106432-2-gabriele.paoloni@intel.com> (raw)
In-Reply-To: <20201127161819.3106432-1-gabriele.paoloni@intel.com>

Currently if mce_end() fails 'no_way_out' is set equal to 'worst'.
'worst' is the worst severity that was found across the MCA banks
associated with the current CPU; however at this point 'no_way_out'
could have been already set by mca_start() by looking at all
severities of all CPUs that entered the MCE handler.
If mce_end() fails, check first if no_way_out is already set and,
if so, stick to it, otherwise use the local worst value.

Cc: <stable@vger.kernel.org>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
---
 arch/x86/kernel/cpu/mce/core.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 4102b866e7c0..32b7099e3511 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1384,8 +1384,10 @@ noinstr void do_machine_check(struct pt_regs *regs)
 	 * When there's any problem use only local no_way_out state.
 	 */
 	if (!lmce) {
-		if (mce_end(order) < 0)
-			no_way_out = worst >= MCE_PANIC_SEVERITY;
+		if (mce_end(order) < 0) {
+			if (!no_way_out)
+				no_way_out = worst >= MCE_PANIC_SEVERITY;
+		}
 	} else {
 		/*
 		 * If there was a fatal machine check we should have
-- 
2.20.1

---------------------------------------------------------------------
INTEL CORPORATION ITALIA S.p.A. con unico socio
Sede: Milanofiori Palazzo E 4 
CAP 20094 Assago (MI)
Capitale Sociale Euro 104.000,00 interamente versato
Partita I.V.A. e Codice Fiscale  04236760155
Repertorio Economico Amministrativo n. 997124 
Registro delle Imprese di Milano nr. 183983/5281/33
Soggetta ad attivita' di direzione e coordinamento di 
INTEL CORPORATION, USA

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.


WARNING: multiple messages have this Message-ID (diff)
From: "Paoloni, Gabriele" <gabriele.paoloni@intel.com>
To: tony.luck@intel.com, bp@alien8.de, tglx@linutronix.de,
	mingo@redhat.com, x86@kernel.org, hpa@zytor.com,
	linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org
Cc: gabriele.paoloni@intel.com, linux-safety@lists.elisa.tech
Subject: [linux-safety] [PATCH v2 1/5] x86/mce: do not overwrite no_way_out if mce_end() fails
Date: Fri, 27 Nov 2020 16:18:15 +0000	[thread overview]
Message-ID: <20201127161819.3106432-2-gabriele.paoloni@intel.com> (raw)
In-Reply-To: <20201127161819.3106432-1-gabriele.paoloni@intel.com>

Currently if mce_end() fails 'no_way_out' is set equal to 'worst'.
'worst' is the worst severity that was found across the MCA banks
associated with the current CPU; however at this point 'no_way_out'
could have been already set by mca_start() by looking at all
severities of all CPUs that entered the MCE handler.
If mce_end() fails, check first if no_way_out is already set and,
if so, stick to it, otherwise use the local worst value.

Cc: <stable@vger.kernel.org>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
---
 arch/x86/kernel/cpu/mce/core.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 4102b866e7c0..32b7099e3511 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1384,8 +1384,10 @@ noinstr void do_machine_check(struct pt_regs *regs)
 	 * When there's any problem use only local no_way_out state.
 	 */
 	if (!lmce) {
-		if (mce_end(order) < 0)
-			no_way_out = worst >= MCE_PANIC_SEVERITY;
+		if (mce_end(order) < 0) {
+			if (!no_way_out)
+				no_way_out = worst >= MCE_PANIC_SEVERITY;
+		}
 	} else {
 		/*
 		 * If there was a fatal machine check we should have
-- 
2.20.1

---------------------------------------------------------------------
INTEL CORPORATION ITALIA S.p.A. con unico socio
Sede: Milanofiori Palazzo E 4 
CAP 20094 Assago (MI)
Capitale Sociale Euro 104.000,00 interamente versato
Partita I.V.A. e Codice Fiscale  04236760155
Repertorio Economico Amministrativo n. 997124 
Registro delle Imprese di Milano nr. 183983/5281/33
Soggetta ad attivita' di direzione e coordinamento di 
INTEL CORPORATION, USA

This e-mail and any attachments may contain confidential material for
the sole use of the intended recipient(s). Any review or distribution
by others is strictly prohibited. If you are not the intended
recipient, please contact the sender and delete all copies.



-=-=-=-=-=-=-=-=-=-=-=-
Links: You receive all messages sent to this group.
View/Reply Online (#208): https://lists.elisa.tech/g/linux-safety/message/208
Mute This Topic: https://lists.elisa.tech/mt/78549944/5278000
Group Owner: linux-safety+owner@lists.elisa.tech
Unsubscribe: https://lists.elisa.tech/g/linux-safety/unsub [linux-safety@archiver.kernel.org]
-=-=-=-=-=-=-=-=-=-=-=-



  reply	other threads:[~2020-11-27 16:18 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-11-27 16:18 [PATCH v2 0/5] x86/MCE: some minor fixes Gabriele Paoloni
2020-11-27 16:18 ` [linux-safety] " Paoloni, Gabriele
2020-11-27 16:18 ` Gabriele Paoloni [this message]
2020-11-27 16:18   ` [linux-safety] [PATCH v2 1/5] x86/mce: do not overwrite no_way_out if mce_end() fails Paoloni, Gabriele
2020-11-27 16:43   ` [tip: x86/urgent] x86/mce: Do " tip-bot2 for Gabriele Paoloni
2020-11-27 16:18 ` [PATCH v2 2/5] x86/mce: move the mce_panic() call and 'kill_it' assignments to the right places Gabriele Paoloni
2020-11-27 16:18   ` [linux-safety] " Paoloni, Gabriele
2020-12-01 18:05   ` [tip: ras/core] x86/mce: Move " tip-bot2 for Gabriele Paoloni
2020-11-27 16:18 ` [PATCH v2 3/5] x86/mce: for LMCE panic only if mca_cfg.tolerant < 3 Gabriele Paoloni
2020-11-27 16:18   ` [linux-safety] " Paoloni, Gabriele
2020-12-01 18:05   ` [tip: ras/core] x86/mce: Panic for LMCE " tip-bot2 for Gabriele Paoloni
2020-11-27 16:18 ` [PATCH v2 4/5] x86/mce: remove redundant call to irq_work_queue() Gabriele Paoloni
2020-11-27 16:18   ` [linux-safety] " Paoloni, Gabriele
2020-12-01 18:05   ` [tip: ras/core] x86/mce: Remove " tip-bot2 for Gabriele Paoloni
2020-11-27 16:18 ` [PATCH v2 5/5] x86/mce: rename kill_it as kill_current_task Gabriele Paoloni
2020-11-27 16:18   ` [linux-safety] " Paoloni, Gabriele
2020-12-01 18:05   ` [tip: ras/core] x86/mce: Rename kill_it to kill_current_task tip-bot2 for Gabriele Paoloni

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=20201127161819.3106432-2-gabriele.paoloni@intel.com \
    --to=gabriele.paoloni@intel.com \
    --cc=bp@alien8.de \
    --cc=hpa@zytor.com \
    --cc=linux-edac@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-safety@lists.elisa.tech \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=tony.luck@intel.com \
    --cc=x86@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.