From f0e2efcfd271733119cfe499f5811968544cbe7b Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Thu, 21 May 2015 09:26:19 -0700 Subject: pstore: do not use message compression without lock pstore_compress() uses static stream buffer for zlib-deflate which easily crashes when several concurrent threads use one shared state. Signed-off-by: Konstantin Khlebnikov Signed-off-by: Tony Luck --- fs/pstore/platform.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index c4c9a10c5760..de525ec0b490 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -299,7 +299,7 @@ static void pstore_dump(struct kmsg_dumper *dumper, bool compressed; size_t total_len; - if (big_oops_buf) { + if (big_oops_buf && is_locked) { dst = big_oops_buf; hsize = sprintf(dst, "%s#%d Part%u\n", why, oopscount, part); -- cgit v1.2.3 From 42222c2a5d5da7fe4839491d5c44034f40761071 Mon Sep 17 00:00:00 2001 From: Wang Long Date: Thu, 21 May 2015 09:34:22 -0700 Subject: fs/pstore: update the backend parameter in pstore module This patch update the module parameter backend, so it is visible through /sys/module/pstore/parameters/backend. For example: if pstore backend is ramoops, with this patch: # cat /sys/module/pstore/parameters/backend ramoops and without this patch: # cat /sys/module/pstore/parameters/backend (null) Signed-off-by: Wang Long Acked-by: Mark Salyzyn Signed-off-by: Tony Luck --- fs/pstore/platform.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index de525ec0b490..791743deedf1 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -456,6 +456,12 @@ int pstore_register(struct pstore_info *psi) add_timer(&pstore_timer); } + /* + * Update the module parameter backend, so it is visible + * through /sys/module/pstore/parameters/backend + */ + backend = psi->name; + pr_info("Registered %s as persistent store backend\n", psi->name); return 0; -- cgit v1.2.3 From 07239fc854ec61b3cdc400d2a50d322d39c673f6 Mon Sep 17 00:00:00 2001 From: long.wanglong Date: Thu, 21 May 2015 09:47:22 -0700 Subject: fs/pstore: Optimization function ramoops_init_przs The value of cxt->record_size does not change in the loop, so this patch optimize the assign statement by dropping sz entirely and using cxt->record_size in its place. Signed-off-by: Wang Long Acked-by: Kees Cook Signed-off-by: Tony Luck --- fs/pstore/ram.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 44a549beeafa..f29373d299b0 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -394,18 +394,16 @@ static int ramoops_init_przs(struct device *dev, struct ramoops_context *cxt, } for (i = 0; i < cxt->max_dump_cnt; i++) { - size_t sz = cxt->record_size; - - cxt->przs[i] = persistent_ram_new(*paddr, sz, 0, + cxt->przs[i] = persistent_ram_new(*paddr, cxt->record_size, 0, &cxt->ecc_info, cxt->memtype); if (IS_ERR(cxt->przs[i])) { err = PTR_ERR(cxt->przs[i]); dev_err(dev, "failed to request mem region (0x%zx@0x%llx): %d\n", - sz, (unsigned long long)*paddr, err); + cxt->record_size, (unsigned long long)*paddr, err); goto fail_prz; } - *paddr += sz; + *paddr += cxt->record_size; } return 0; -- cgit v1.2.3 From e036bd330d21e929e94ed4d5432f9d279b19ce47 Mon Sep 17 00:00:00 2001 From: Ben Zhang Date: Thu, 21 May 2015 09:50:34 -0700 Subject: pstore/ram: verify ramoops header before saving record On some devices the persistent memory contains junk after a cold boot, and /dev/pstore/dmesg-ramoops-* are created with random data which is not the result of a kernel crash. This patch adds a ramoops header check and skips any persistent_ram_zone that does not have a valid header. Signed-off-by: Ben Zhang Signed-off-by: Tony Luck --- fs/pstore/ram.c | 40 ++++++++++++++++++++++++++++------------ 1 file changed, 28 insertions(+), 12 deletions(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index f29373d299b0..d84ce222c516 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -186,12 +186,34 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, ssize_t size; ssize_t ecc_notice_size; struct ramoops_context *cxt = psi->data; - struct persistent_ram_zone *prz; - int header_length; + struct persistent_ram_zone *prz = NULL; + int header_length = 0; + + /* Ramoops headers provide time stamps for PSTORE_TYPE_DMESG, but + * PSTORE_TYPE_CONSOLE and PSTORE_TYPE_FTRACE don't currently have + * valid time stamps, so it is initialized to zero. + */ + time->tv_sec = 0; + time->tv_nsec = 0; + *compressed = false; + + /* Find the next valid persistent_ram_zone for DMESG */ + while (cxt->dump_read_cnt < cxt->max_dump_cnt && !prz) { + prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt, + cxt->max_dump_cnt, id, type, + PSTORE_TYPE_DMESG, 1); + if (!prz_ok(prz)) + continue; + header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz), + time, compressed); + /* Clear and skip this DMESG record if it has no valid header */ + if (!header_length) { + persistent_ram_free_old(prz); + persistent_ram_zap(prz); + prz = NULL; + } + } - prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt, - cxt->max_dump_cnt, id, type, - PSTORE_TYPE_DMESG, 1); if (!prz_ok(prz)) prz = ramoops_get_next_prz(&cxt->cprz, &cxt->console_read_cnt, 1, id, type, PSTORE_TYPE_CONSOLE, 0); @@ -204,13 +226,7 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, if (!prz_ok(prz)) return 0; - if (!persistent_ram_old(prz)) - return 0; - - size = persistent_ram_old_size(prz); - header_length = ramoops_read_kmsg_hdr(persistent_ram_old(prz), time, - compressed); - size -= header_length; + size = persistent_ram_old_size(prz) - header_length; /* ECC correction notice */ ecc_notice_size = persistent_ram_ecc_string(prz, NULL, 0); -- cgit v1.2.3 From 078550569eafc6631d333488045159badbeb911a Mon Sep 17 00:00:00 2001 From: Wang Long Date: Thu, 21 May 2015 09:52:29 -0700 Subject: ramoops: make it possible to change mem_type param. If we set ramoops.mem_type=1 in command line, the current code can not change mem_type to 1, because it is assigned to 0 in function ramoops_register_dummy. This patch make it possible to change mem_type parameter in command line. Signed-off-by: Wang Long Acked-by: Tony Lindgren Signed-off-by: Tony Luck --- fs/pstore/ram.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index d84ce222c516..6c26c4daaec9 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -622,7 +622,7 @@ static void ramoops_register_dummy(void) dummy_data->mem_size = mem_size; dummy_data->mem_address = mem_address; - dummy_data->mem_type = 0; + dummy_data->mem_type = mem_type; dummy_data->record_size = record_size; dummy_data->console_size = ramoops_console_size; dummy_data->ftrace_size = ramoops_ftrace_size; -- cgit v1.2.3