Linux-EDAC Archive on lore.kernel.org
 help / color / Atom feed
From: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
To: linux@dominikbrodowski.net, tony.luck@intel.com, bp@alien8.de,
	tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com
Cc: x86@kernel.org, linux-edac@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Subject: [PATCH] x86/mce/therm_throt: Avoid updating RO and reserved bits
Date: Thu, 28 Nov 2019 07:08:24 -0800
Message-ID: <20191128150824.22413-1-srinivas.pandruvada@linux.intel.com> (raw)

While writing to MSR IA32_THERM_STATUS/IA32_PKG_THERM_STATUS, avoid
writing 1 to read only and reserved fields. Updating some fields
generates exception.

Fixes: f6656208f04e ("x86/mce/therm_throt: Optimize notifications of thermal throttle")
Reported-by: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
---
 arch/x86/kernel/cpu/mce/therm_throt.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/therm_throt.c b/arch/x86/kernel/cpu/mce/therm_throt.c
index d01e0da0163a..80be4a5ac303 100644
--- a/arch/x86/kernel/cpu/mce/therm_throt.c
+++ b/arch/x86/kernel/cpu/mce/therm_throt.c
@@ -195,17 +195,24 @@ static const struct attribute_group thermal_attr_group = {
 #define THERM_THROT_POLL_INTERVAL	HZ
 #define THERM_STATUS_PROCHOT_LOG	BIT(1)
 
+#define THERM_STATUS_CLEAR_CORE_MASK (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11) | BIT(13) | BIT(15))
+#define THERM_STATUS_CLEAR_PKG_MASK (BIT(1) | BIT(3) | BIT(5) | BIT(7) | BIT(9) | BIT(11))
+
 static void clear_therm_status_log(int level)
 {
 	int msr;
-	u64 msr_val;
+	u64 mask, msr_val;
 
-	if (level == CORE_LEVEL)
+	if (level == CORE_LEVEL) {
 		msr = MSR_IA32_THERM_STATUS;
-	else
+		mask = THERM_STATUS_CLEAR_CORE_MASK;
+	} else {
 		msr = MSR_IA32_PACKAGE_THERM_STATUS;
+		mask = THERM_STATUS_CLEAR_PKG_MASK;
+	}
 
 	rdmsrl(msr, msr_val);
+	msr_val &= mask;
 	wrmsrl(msr, msr_val & ~THERM_STATUS_PROCHOT_LOG);
 }
 
-- 
2.17.2


             reply index

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-28 15:08 Srinivas Pandruvada [this message]
2019-11-29  8:29 ` [tip: ras/urgent] x86/mce/therm_throt: Mask out read-only and reserved MSR bits tip-bot2 for Srinivas Pandruvada

Reply instructions:

You may reply publically 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=20191128150824.22413-1-srinivas.pandruvada@linux.intel.com \
    --to=srinivas.pandruvada@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=hpa@zytor.com \
    --cc=linux-edac@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@dominikbrodowski.net \
    --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

Linux-EDAC Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-edac/0 linux-edac/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-edac linux-edac/ https://lore.kernel.org/linux-edac \
		linux-edac@vger.kernel.org
	public-inbox-index linux-edac

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-edac


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git