lkml.org 
[lkml]   [2014]   [Dec]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] x86, mce: use mce_usable_address() for UCNA memory error recovery
Date
A machine-check address register (MCi_ADDR) that the processor uses
to report the address or location associated with the logged error.
The address field can hold a virtual (linear) address, a physical
address, or a value indicating an internal physical location, depending
on the type of error. For further information, see the documentation
for particular implementations of the architecture.
-- AMD64 APM Volume 2

The IA32_MCi_ADDR MSR contains the address of the code or data memory
location that produced the machine-check error. The IA32_MCi_ADDR
register is either not implemented or contains no address if the ADDRV
flag in the IA32_MCi_STATUS register is clear. The address returned is
an offset into a segment, linear address, physical address, or memory
address. This depends on the error encountered.
-- Intel SDM Volume 3B

As the comment of `mce_usable_address' suggests, we should check if the
address reported by the CPU is in a format we can parse. This patch aims
to use mce_usable_address() for UCNA/Deferred memory error recovery. For
Intel x86_64 platform mce_usable_address() can work fine, but it doesn't
even matter for AMD platform.

Signed-off-by: Chen Yucong <slaoub@gmail.com>
---
arch/x86/kernel/cpu/mcheck/mce.c | 48 ++++++++++++++++++++++++--------------
1 file changed, 30 insertions(+), 18 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 800d423..c777626 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -607,6 +607,35 @@ static bool memory_error(struct mce *m)
return false;
}

+/*
+ * Check if the address reported by the CPU is in a format we can parse.
+ * It would be possible to add code for most other cases, but all would
+ * be somewhat complicated (e.g. segment offset would require an instruction
+ * parser). So only support physical addresses up to page granuality for now.
+ */
+static int mce_usable_address(struct mce *m)
+{
+ struct cpuinfo_x86 *c = &boot_cpu_data;
+
+ if (c->x86_vendor == X86_VENDOR_INTEL) {
+ if (!(m->status & MCI_STATUS_MISCV) ||
+ !(m->status & MCI_STATUS_ADDRV))
+ return 0;
+ if (MCI_MISC_ADDR_LSB(m->misc) > PAGE_SHIFT)
+ return 0;
+ if (MCI_MISC_ADDR_MODE(m->misc) != MCI_MISC_ADDR_PHYS)
+ return 0;
+ return 1;
+ } else if (c->x86_vendor == X86_VENDOR_AMD) {
+ /*
+ * coming soon
+ */
+ return 0;
+ }
+
+ return 0;
+}
+
DEFINE_PER_CPU(unsigned, mce_poll_count);

/*
@@ -671,7 +700,7 @@ void machine_check_poll(enum mcp_flags flags, mce_banks_t *b)
* do not add it into the ring buffer.
*/
if (severity == MCE_DEFERRED_SEVERITY && memory_error(&m)) {
- if (m.status & MCI_STATUS_ADDRV) {
+ if (mce_usable_address(&m)) {
mce_ring_add(m.addr >> PAGE_SHIFT);
mce_schedule_work();
}
@@ -976,23 +1005,6 @@ reset:
return ret;
}

-/*
- * Check if the address reported by the CPU is in a format we can parse.
- * It would be possible to add code for most other cases, but all would
- * be somewhat complicated (e.g. segment offset would require an instruction
- * parser). So only support physical addresses up to page granuality for now.
- */
-static int mce_usable_address(struct mce *m)
-{
- if (!(m->status & MCI_STATUS_MISCV) || !(m->status & MCI_STATUS_ADDRV))
- return 0;
- if (MCI_MISC_ADDR_LSB(m->misc) > PAGE_SHIFT)
- return 0;
- if (MCI_MISC_ADDR_MODE(m->misc) != MCI_MISC_ADDR_PHYS)
- return 0;
- return 1;
-}
-
static void mce_clear_state(unsigned long *toclear)
{
int i;
--
1.7.10.4


\
 
 \ /
  Last update: 2014-12-29 07:21    [W:0.042 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site