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Merge branch 'ras-core-for-linus' of git://git.kernel.org/pub/scm/lin…
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…ux/kernel/git/tip/tip

Pull x86 RAS updates from Thomas Gleixner:

 - 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.

* 'ras-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/MCE/AMD: Read MCx_MISC block addresses on any CPU
  x86/MCE: Fix stack out-of-bounds write in mce-inject.c: Flags_read()
  x86/MCE: Enable MCE broadcasting on new Centaur CPUs
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torvalds committed Jun 5, 2018
2 parents db020be + fbf96cf commit 0ef283d
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Showing 3 changed files with 26 additions and 9 deletions.
2 changes: 1 addition & 1 deletion arch/x86/kernel/cpu/mcheck/mce-inject.c
Original file line number Diff line number Diff line change
Expand Up @@ -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 {
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18 changes: 18 additions & 0 deletions arch/x86/kernel/cpu/mcheck/mce.c
Original file line number Diff line number Diff line change
Expand Up @@ -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) {
Expand All @@ -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;
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15 changes: 7 additions & 8 deletions arch/x86/kernel/cpu/mcheck/mce_amd.c
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand All @@ -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);

Expand All @@ -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;
Expand All @@ -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) {
Expand Down Expand Up @@ -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;

Expand Down Expand Up @@ -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;

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