[GIT pull] RAS updates for 4.18

From: Thomas Gleixner
Date: Mon Jun 04 2018 - 06:10:18 EST


Linus,

please pull the latest ras-core-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git ras-core-for-linus

A small set of updates for RAS/MCE:

- Fix a stack out of bounds write in the MCE error injection code.

- Avoid IPIs during CPU hotplug to read the MCx_MISC block address from a
remote CPU. That's fragile and pointless because the block addresses are
the same on all CPUs. So they can be read once and local.

- Add support for MCE broadcasting on newer VIA Centaur CPUs.

Thanks,

tglx

------------------>
Borislav Petkov (1):
x86/MCE/AMD: Read MCx_MISC block addresses on any CPU

David Wang (1):
x86/MCE: Enable MCE broadcasting on new Centaur CPUs

Tony Luck (1):
x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read()


arch/x86/kernel/cpu/mcheck/mce-inject.c | 2 +-
arch/x86/kernel/cpu/mcheck/mce.c | 18 ++++++++++++++++++
arch/x86/kernel/cpu/mcheck/mce_amd.c | 15 +++++++--------
3 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce-inject.c b/arch/x86/kernel/cpu/mcheck/mce-inject.c
index 475cb4f5f14f..c805a06e14c3 100644
--- a/arch/x86/kernel/cpu/mcheck/mce-inject.c
+++ b/arch/x86/kernel/cpu/mcheck/mce-inject.c
@@ -48,7 +48,7 @@ static struct dentry *dfs_inj;

static u8 n_banks;

-#define MAX_FLAG_OPT_SIZE 3
+#define MAX_FLAG_OPT_SIZE 4
#define NBCFG 0x44

enum injection_type {
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index 42cf2880d0ed..cd76380af79f 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1727,6 +1727,21 @@ static void __mcheck_cpu_init_early(struct cpuinfo_x86 *c)
}
}

+static void mce_centaur_feature_init(struct cpuinfo_x86 *c)
+{
+ struct mca_config *cfg = &mca_cfg;
+
+ /*
+ * All newer Centaur CPUs support MCE broadcasting. Enable
+ * synchronization with a one second timeout.
+ */
+ if ((c->x86 == 6 && c->x86_model == 0xf && c->x86_stepping >= 0xe) ||
+ c->x86 > 6) {
+ if (cfg->monarch_timeout < 0)
+ cfg->monarch_timeout = USEC_PER_SEC;
+ }
+}
+
static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
{
switch (c->x86_vendor) {
@@ -1739,6 +1754,9 @@ static void __mcheck_cpu_init_vendor(struct cpuinfo_x86 *c)
mce_amd_feature_init(c);
break;
}
+ case X86_VENDOR_CENTAUR:
+ mce_centaur_feature_init(c);
+ break;

default:
break;
diff --git a/arch/x86/kernel/cpu/mcheck/mce_amd.c b/arch/x86/kernel/cpu/mcheck/mce_amd.c
index c8e038800591..f591b01930db 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_amd.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c
@@ -436,8 +436,7 @@ static void deferred_error_interrupt_enable(struct cpuinfo_x86 *c)
wrmsr(MSR_CU_DEF_ERR, low, high);
}

-static u32 smca_get_block_address(unsigned int cpu, unsigned int bank,
- unsigned int block)
+static u32 smca_get_block_address(unsigned int bank, unsigned int block)
{
u32 low, high;
u32 addr = 0;
@@ -456,13 +455,13 @@ static u32 smca_get_block_address(unsigned int cpu, unsigned int bank,
* For SMCA enabled processors, BLKPTR field of the first MISC register
* (MCx_MISC0) indicates presence of additional MISC regs set (MISC1-4).
*/
- if (rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
+ if (rdmsr_safe(MSR_AMD64_SMCA_MCx_CONFIG(bank), &low, &high))
goto out;

if (!(low & MCI_CONFIG_MCAX))
goto out;

- if (!rdmsr_safe_on_cpu(cpu, MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high) &&
+ if (!rdmsr_safe(MSR_AMD64_SMCA_MCx_MISC(bank), &low, &high) &&
(low & MASK_BLKPTR_LO))
addr = MSR_AMD64_SMCA_MCx_MISCy(bank, block - 1);

@@ -471,7 +470,7 @@ static u32 smca_get_block_address(unsigned int cpu, unsigned int bank,
return addr;
}

-static u32 get_block_address(unsigned int cpu, u32 current_addr, u32 low, u32 high,
+static u32 get_block_address(u32 current_addr, u32 low, u32 high,
unsigned int bank, unsigned int block)
{
u32 addr = 0, offset = 0;
@@ -480,7 +479,7 @@ static u32 get_block_address(unsigned int cpu, u32 current_addr, u32 low, u32 hi
return addr;

if (mce_flags.smca)
- return smca_get_block_address(cpu, bank, block);
+ return smca_get_block_address(bank, block);

/* Fall back to method we used for older processors: */
switch (block) {
@@ -558,7 +557,7 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
smca_configure(bank, cpu);

for (block = 0; block < NR_BLOCKS; ++block) {
- address = get_block_address(cpu, address, low, high, bank, block);
+ address = get_block_address(address, low, high, bank, block);
if (!address)
break;

@@ -1175,7 +1174,7 @@ static int allocate_threshold_blocks(unsigned int cpu, unsigned int bank,
if (err)
goto out_free;
recurse:
- address = get_block_address(cpu, address, low, high, bank, ++block);
+ address = get_block_address(address, low, high, bank, ++block);
if (!address)
return 0;