diff options
Diffstat (limited to 'fs/pstore')
| -rw-r--r-- | fs/pstore/platform.c | 28 |
1 files changed, 21 insertions, 7 deletions
diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index ca60ebcfb15..0472924024c 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -28,6 +28,7 @@ #include <linux/timer.h> #include <linux/slab.h> #include <linux/uaccess.h> +#include <linux/hardirq.h> #include <linux/workqueue.h> #include "internal.h" @@ -88,13 +89,20 @@ static void pstore_dump(struct kmsg_dumper *dumper, u64 id; int hsize; unsigned int part = 1; + unsigned long flags = 0; + int is_locked = 0; if (reason < ARRAY_SIZE(reason_str)) why = reason_str[reason]; else why = "Unknown"; - mutex_lock(&psinfo->buf_mutex); + if (in_nmi()) { + is_locked = spin_trylock(&psinfo->buf_lock); + if (!is_locked) + pr_err("pstore dump routine blocked in NMI, may corrupt error record\n"); + } else + spin_lock_irqsave(&psinfo->buf_lock, flags); oopscount++; while (total < kmsg_bytes) { dst = psinfo->buf; @@ -123,7 +131,11 @@ static void pstore_dump(struct kmsg_dumper *dumper, total += l1_cpy + l2_cpy; part++; } - mutex_unlock(&psinfo->buf_mutex); + if (in_nmi()) { + if (is_locked) + spin_unlock(&psinfo->buf_lock); + } else + spin_unlock_irqrestore(&psinfo->buf_lock, flags); } static struct kmsg_dumper pstore_dumper = { @@ -188,11 +200,12 @@ void pstore_get_records(int quiet) enum pstore_type_id type; struct timespec time; int failed = 0, rc; + unsigned long flags; if (!psi) return; - mutex_lock(&psinfo->buf_mutex); + spin_lock_irqsave(&psinfo->buf_lock, flags); rc = psi->open(psi); if (rc) goto out; @@ -205,7 +218,7 @@ void pstore_get_records(int quiet) } psi->close(psi); out: - mutex_unlock(&psinfo->buf_mutex); + spin_unlock_irqrestore(&psinfo->buf_lock, flags); if (failed) printk(KERN_WARNING "pstore: failed to load %d record(s) from '%s'\n", @@ -233,7 +246,8 @@ static void pstore_timefunc(unsigned long dummy) */ int pstore_write(enum pstore_type_id type, char *buf, size_t size) { - u64 id; + u64 id; + unsigned long flags; if (!psinfo) return -ENODEV; @@ -241,13 +255,13 @@ int pstore_write(enum pstore_type_id type, char *buf, size_t size) if (size > psinfo->bufsize) return -EFBIG; - mutex_lock(&psinfo->buf_mutex); + spin_lock_irqsave(&psinfo->buf_lock, flags); memcpy(psinfo->buf, buf, size); id = psinfo->write(type, 0, size, psinfo); if (pstore_is_mounted()) pstore_mkfile(PSTORE_TYPE_DMESG, psinfo->name, id, psinfo->buf, size, CURRENT_TIME, psinfo); - mutex_unlock(&psinfo->buf_mutex); + spin_unlock_irqrestore(&psinfo->buf_lock, flags); return 0; } |