When running under Xen as dom0, /dev/mcelog is being provided by Xen
instead of the normal mcelog character device of the MCE core. Convert
an error message being issued by the MCE core in this case to an
informative message that Xen has registered the device.
Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: xen-devel@lists.xenproject.org
Cc: Tony Luck <tony.luck@intel.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20170614084059.19294-1-jgross@suse.com
Static checkers complain about the missing call to misc_deregister() if
bind_virq_for_mce() fails.
Also I reversed the tests so that we do error handling instead of
success handling. That way we just have a series of function calls
instead of the more complicated nested if statements in the original
code. Let's preserve the error codes as well.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Convert printks to pr_<level> (excludes printk(KERN_DEBUG...)
to be more consistent throughout the xen subsystem.
Add pr_fmt with KBUILD_MODNAME or "xen:" KBUILD_MODNAME
Coalesce formats and add missing word spaces
Add missing newlines
Align arguments and reflow to 80 columns
Remove DRV_NAME from formats as pr_fmt adds the same content
This does change some of the prefixes of these messages
but it also does make them more consistent.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
If a driver leaves its poll method NULL, the device is assumed to
be both readable and writable without blocking.
This patch add .poll method to xen mcelog device driver, so that
when mcelog use system calls like ppoll or select, it would be
blocked when no data available, and avoid spinning at CPU.
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
copy_to_user might sleep and print a stack trace if it is executed
in an atomic spinlock context. Like this:
(XEN) CMCI: send CMCI to DOM0 through virq
BUG: sleeping function called from invalid context at /home/konradinux/kernel.h:199
in_atomic(): 1, irqs_disabled(): 0, pid: 4581, name: mcelog
Pid: 4581, comm: mcelog Tainted: G O 3.5.0-rc1upstream-00003-g149000b-dirty #1
[<ffffffff8109ad9a>] __might_sleep+0xda/0x100
[<ffffffff81329b0b>] xen_mce_chrdev_read+0xab/0x140
[<ffffffff81148945>] vfs_read+0xc5/0x190
[<ffffffff81148b0c>] sys_read+0x4c/0x90
[<ffffffff815bd039>] system_call_fastpath+0x16
This patch schedule a workqueue for IRQ handler to poll the data,
and use mutex instead of spinlock, so copy_to_user sleep in atomic
context would not occur.
Reported-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Suggested-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
When MCA error occurs, it would be handled by Xen hypervisor first,
and then the error information would be sent to initial domain for logging.
This patch gets error information from Xen hypervisor and convert
Xen format error into Linux format mcelog. This logic is basically
self-contained, not touching other kernel components.
By using tools like mcelog tool users could read specific error information,
like what they did under native Linux.
To test follow directions outlined in Documentation/acpi/apei/einj.txt
Acked-and-tested-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Ke, Liping <liping.ke@intel.com>
Signed-off-by: Jiang, Yunhong <yunhong.jiang@intel.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Juergen Gross