Commit ff7b862a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'ras_updates_for_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull RAS updates from Borislav Petkov:

 - Do not report spurious MCEs on some Intel platforms caused by errata;
   by Prarit Bhargava.

 - Change dev-mcelog's hardcoded limit of 32 error records to a dynamic
   one, controlled by the number of logical CPUs, by Tony Luck.

 - Add support for the processor identification number (PPIN) on AMD, by
   Wei Huang.

* tag 'ras_updates_for_5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mce/amd: Add PPIN support for AMD MCE
  x86/mce/dev-mcelog: Dynamically allocate space for machine check records
  x86/mce: Do not log spurious corrected mce errors
parents aaf985e2 077168e2

arch/x86/include/asm/cpufeatures.h

+1 −0
Original line number Diff line number Diff line
@@ -299,6 +299,7 @@ 
#define X86_FEATURE_AMD_IBRS		(13*32+14) /* "" Indirect Branch Restricted Speculation */

#define X86_FEATURE_AMD_STIBP		(13*32+15) /* "" Single Thread Indirect Branch Predictors */

#define X86_FEATURE_AMD_STIBP_ALWAYS_ON	(13*32+17) /* "" Single Thread Indirect Branch Predictors always-on preferred */

#define X86_FEATURE_AMD_PPIN		(13*32+23) /* Protected Processor Inventory Number */

#define X86_FEATURE_AMD_SSBD		(13*32+24) /* "" Speculative Store Bypass Disable */

#define X86_FEATURE_VIRT_SSBD		(13*32+25) /* Virtualized Speculative Store Bypass Disable */

#define X86_FEATURE_AMD_SSB_NO		(13*32+26) /* "" Speculative Store Bypass is fixed in hardware. */

arch/x86/include/asm/mce.h

+3 −3
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ 


#define MCE_OVERFLOW 0		/* bit 0 in flags means overflow */



#define MCE_LOG_LEN 32

#define MCE_LOG_MIN_LEN 32U

#define MCE_LOG_SIGNATURE	"MACHINECHECK"



/* AMD Scalable MCA */
@@ -135,11 +135,11 @@ 
 */

struct mce_log_buffer {

	char signature[12]; /* "MACHINECHECK" */

	unsigned len;	    /* = MCE_LOG_LEN */

	unsigned len;	    /* = elements in .mce_entry[] */

	unsigned next;

	unsigned flags;

	unsigned recordlen;	/* length of struct mce */

	struct mce entry[MCE_LOG_LEN];

	struct mce entry[];

};



enum mce_notifier_prios {

arch/x86/kernel/cpu/amd.c

+30 −0
Original line number Diff line number Diff line
@@ -394,6 +394,35 @@ static void amd_detect_cmp(struct cpuinfo_x86 *c) 
	per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;

}



static void amd_detect_ppin(struct cpuinfo_x86 *c)

{

	unsigned long long val;



	if (!cpu_has(c, X86_FEATURE_AMD_PPIN))

		return;



	/* When PPIN is defined in CPUID, still need to check PPIN_CTL MSR */

	if (rdmsrl_safe(MSR_AMD_PPIN_CTL, &val))

		goto clear_ppin;



	/* PPIN is locked in disabled mode, clear feature bit */

	if ((val & 3UL) == 1UL)

		goto clear_ppin;



	/* If PPIN is disabled, try to enable it */

	if (!(val & 2UL)) {

		wrmsrl_safe(MSR_AMD_PPIN_CTL,  val | 2UL);

		rdmsrl_safe(MSR_AMD_PPIN_CTL, &val);

	}



	/* If PPIN_EN bit is 1, return from here; otherwise fall through */

	if (val & 2UL)

		return;



clear_ppin:

	clear_cpu_cap(c, X86_FEATURE_AMD_PPIN);

}



u16 amd_get_nb_id(int cpu)

{

	return per_cpu(cpu_llc_id, cpu);
@@ -941,6 +970,7 @@ static void init_amd(struct cpuinfo_x86 *c) 
	amd_detect_cmp(c);

	amd_get_topology(c);

	srat_detect_node(c);

	amd_detect_ppin(c);



	init_amd_cacheinfo(c);

arch/x86/kernel/cpu/mce/core.c

+4 −0
Original line number Diff line number Diff line
@@ -142,6 +142,8 @@ void mce_setup(struct mce *m) 


	if (this_cpu_has(X86_FEATURE_INTEL_PPIN))

		rdmsrl(MSR_PPIN, m->ppin);

	else if (this_cpu_has(X86_FEATURE_AMD_PPIN))

		rdmsrl(MSR_AMD_PPIN, m->ppin);



	m->microcode = boot_cpu_data.microcode;

}
@@ -1877,6 +1879,8 @@ bool filter_mce(struct mce *m) 
{

	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD)

		return amd_filter_mce(m);

	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)

		return intel_filter_mce(m);



	return false;

}

arch/x86/kernel/cpu/mce/dev-mcelog.c

+27 −20
Original line number Diff line number Diff line
@@ -29,11 +29,7 @@ static char *mce_helper_argv[2] = { mce_helper, NULL }; 
 * separate MCEs from kernel messages to avoid bogus bug reports.

 */



static struct mce_log_buffer mcelog = {

	.signature	= MCE_LOG_SIGNATURE,

	.len		= MCE_LOG_LEN,

	.recordlen	= sizeof(struct mce),

};

static struct mce_log_buffer *mcelog;



static DECLARE_WAIT_QUEUE_HEAD(mce_chrdev_wait);
@@ -45,21 +41,21 @@ static int dev_mce_log(struct notifier_block *nb, unsigned long val, 


	mutex_lock(&mce_chrdev_read_mutex);



	entry = mcelog.next;

	entry = mcelog->next;



	/*

	 * When the buffer fills up discard new entries. Assume that the

	 * earlier errors are the more interesting ones:

	 */

	if (entry >= MCE_LOG_LEN) {

		set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog.flags);

	if (entry >= mcelog->len) {

		set_bit(MCE_OVERFLOW, (unsigned long *)&mcelog->flags);

		goto unlock;

	}



	mcelog.next = entry + 1;

	mcelog->next = entry + 1;



	memcpy(mcelog.entry + entry, mce, sizeof(struct mce));

	mcelog.entry[entry].finished = 1;

	memcpy(mcelog->entry + entry, mce, sizeof(struct mce));

	mcelog->entry[entry].finished = 1;



	/* wake processes polling /dev/mcelog */

	wake_up_interruptible(&mce_chrdev_wait);
@@ -214,21 +210,21 @@ static ssize_t mce_chrdev_read(struct file *filp, char __user *ubuf, 


	/* Only supports full reads right now */

	err = -EINVAL;

	if (*off != 0 || usize < MCE_LOG_LEN*sizeof(struct mce))

	if (*off != 0 || usize < mcelog->len * sizeof(struct mce))

		goto out;



	next = mcelog.next;

	next = mcelog->next;

	err = 0;



	for (i = 0; i < next; i++) {

		struct mce *m = &mcelog.entry[i];

		struct mce *m = &mcelog->entry[i];



		err |= copy_to_user(buf, m, sizeof(*m));

		buf += sizeof(*m);

	}



	memset(mcelog.entry, 0, next * sizeof(struct mce));

	mcelog.next = 0;

	memset(mcelog->entry, 0, next * sizeof(struct mce));

	mcelog->next = 0;



	if (err)

		err = -EFAULT;
@@ -242,7 +238,7 @@ out: 
static __poll_t mce_chrdev_poll(struct file *file, poll_table *wait)

{

	poll_wait(file, &mce_chrdev_wait, wait);

	if (READ_ONCE(mcelog.next))

	if (READ_ONCE(mcelog->next))

		return EPOLLIN | EPOLLRDNORM;

	if (!mce_apei_read_done && apei_check_mce())

		return EPOLLIN | EPOLLRDNORM;
@@ -261,13 +257,13 @@ static long mce_chrdev_ioctl(struct file *f, unsigned int cmd, 
	case MCE_GET_RECORD_LEN:

		return put_user(sizeof(struct mce), p);

	case MCE_GET_LOG_LEN:

		return put_user(MCE_LOG_LEN, p);

		return put_user(mcelog->len, p);

	case MCE_GETCLEAR_FLAGS: {

		unsigned flags;



		do {

			flags = mcelog.flags;

		} while (cmpxchg(&mcelog.flags, flags, 0) != flags);

			flags = mcelog->flags;

		} while (cmpxchg(&mcelog->flags, flags, 0) != flags);



		return put_user(flags, p);

	}
@@ -339,8 +335,18 @@ static struct miscdevice mce_chrdev_device = { 


static __init int dev_mcelog_init_device(void)

{

	int mce_log_len;

	int err;



	mce_log_len = max(MCE_LOG_MIN_LEN, num_online_cpus());

	mcelog = kzalloc(sizeof(*mcelog) + mce_log_len * sizeof(struct mce), GFP_KERNEL);

	if (!mcelog)

		return -ENOMEM;



	strncpy(mcelog->signature, MCE_LOG_SIGNATURE, sizeof(mcelog->signature));

	mcelog->len = mce_log_len;

	mcelog->recordlen = sizeof(struct mce);



	/* register character device /dev/mcelog */

	err = misc_register(&mce_chrdev_device);

	if (err) {
@@ -350,6 +356,7 @@ static __init int dev_mcelog_init_device(void) 
		else

			pr_err("Unable to init device /dev/mcelog (rc: %d)\n", err);



		kfree(mcelog);

		return err;

	}

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