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From: Greg KH <gregkh@suse.de>
To: linux-kernel@vger.kernel.org, stable@vger.kernel.org
Cc: torvalds@linux-foundation.org, akpm@linux-foundation.org,
	alan@lxorguk.ukuu.org.uk,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Jesse Barnes <jbarnes@virtuousgeek.org>
Subject: [08/27] PCI: msi: Disable msi interrupts when we initialize a pci device
Date: Mon, 23 Jan 2012 15:40:54 -0800	[thread overview]
Message-ID: <20120123234202.366803070@clark.kroah.org> (raw)
In-Reply-To: <20120123234224.GA19510@kroah.com>

2.6.32-longterm review patch.  If anyone has any objections, please let me know.

------------------

From: "Eric W. Biederman" <ebiederm@xmission.com>

commit a776c491ca5e38c26d9f66923ff574d041e747f4 upstream.

I traced a nasty kexec on panic boot failure to the fact that we had
screaming msi interrupts and we were not disabling the msi messages at
kernel startup.  The booting kernel had not enabled those interupts so
was not prepared to handle them.

I can see no reason why we would ever want to leave the msi interrupts
enabled at boot if something else has enabled those interrupts.  The pci
spec specifies that msi interrupts should be off by default.  Drivers
are expected to enable the msi interrupts if they want to use them.  Our
interrupt handling code reprograms the interrupt handlers at boot and
will not be be able to do anything useful with an unexpected interrupt.

This patch applies cleanly all of the way back to 2.6.32 where I noticed
the problem.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
 drivers/pci/msi.c |   10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -863,5 +863,15 @@ EXPORT_SYMBOL(pci_msi_enabled);
 
 void pci_msi_init_pci_dev(struct pci_dev *dev)
 {
+	int pos;
 	INIT_LIST_HEAD(&dev->msi_list);
+
+	/* Disable the msi hardware to avoid screaming interrupts
+	 * during boot.  This is the power on reset default so
+	 * usually this should be a noop.
+	 */
+	pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
+	if (pos)
+		msi_set_enable(dev, pos, 0);
+	msix_set_enable(dev, 0);
 }



  parent reply	other threads:[~2012-01-23 23:45 UTC|newest]

Thread overview: 31+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-23 23:42 [00/27] 2.6.32.55-longterm review Greg KH
2012-01-23 23:40 ` [01/27] ext4: fix undefined behavior in ext4_fill_flex_info() Greg KH
2012-01-23 23:40 ` [02/27] ALSA: snd-usb-us122l: Delete calls to preempt_disable Greg KH
2012-01-23 23:40 ` [03/27] ALSA: ice1724 - Check for ac97 to avoid kernel oops Greg KH
2012-01-23 23:40 ` [04/27] ALSA: hda - Return the error from get_wcaps_type() for invalid NIDs Greg KH
2012-01-23 23:40 ` [05/27] HID: bump maximum global item tag report size to 96 bytes Greg KH
2012-01-23 23:40 ` [06/27] UBI: fix use-after-free on error path Greg KH
2012-01-23 23:40 ` [07/27] PCI: Fix PCI_EXP_TYPE_RC_EC value Greg KH
2012-01-23 23:40 ` Greg KH [this message]
2012-01-23 23:40 ` [09/27] xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX Greg KH
2012-01-23 23:40 ` [10/27] ima: free duplicate measurement memory Greg KH
2012-01-23 23:40 ` [11/27] PNP: work around Dell 1536/1546 BIOS MMCONFIG bug that breaks USB Greg KH
2012-01-23 23:40 ` [12/27] x86: Fix mmap random address range Greg KH
2012-01-23 23:40 ` [13/27] UBI: fix nameless volumes handling Greg KH
2012-01-23 23:41 ` [14/27] i2c: Fix error value returned by several bus drivers Greg KH
2012-01-23 23:41 ` [15/27] [media] V4L/DVB: v4l2-ioctl: integer overflow in video_usercopy() Greg KH
2012-01-23 23:41 ` [16/27] svcrpc: fix double-free on shutdown of nfsd after changing pool mode Greg KH
2012-01-23 23:41 ` [17/27] svcrpc: destroy server sockets all at once Greg KH
2012-01-23 23:41 ` [18/27] nfsd: Fix oops when parsing a 0 length export Greg KH
2012-01-23 23:41 ` [19/27] USB: cdc-wdm: fix misuse of logical operation in place of bitop Greg KH
2012-01-23 23:41 ` [20/27] [S390] fix cputime overflow in uptime_proc_show Greg KH
2012-01-23 23:41 ` [21/27] USB: Fix bad dma problem on WDM device disconnect Greg KH
2012-01-23 23:41 ` [22/27] block: add and use scsi_blk_cmd_ioctl Greg KH
2012-01-23 23:41 ` [23/27] kernel.h: add printk_ratelimited and pr_<level>_rl Greg KH
2012-01-24 14:46   ` Phil Carmody
2012-01-24 16:35     ` Ben Hutchings
2012-01-24 16:43       ` Greg KH
2012-01-23 23:41 ` [24/27] ALSA: HDA: Fix internal microphone on Dell Studio 16 XPS 1645 Greg KH
2012-01-23 23:41 ` [25/27] [SCSI] sym53c8xx: Fix NULL pointer dereference in slave_destroy Greg KH
2012-01-23 23:41 ` [26/27] score: fix off-by-one index into syscall table Greg KH
2012-01-23 23:41 ` [27/27] kprobes: initialize before using a hlist Greg KH

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