Each struct ghes has an worst-case sized buffer for storing the estatus. If an error is being processed by ghes_proc() in process context this buffer will be in use. If the error source then triggers an NMI-like notification, the same buffer will be used by _in_nmi_notify_one() to stage the estatus data, before __process_error() copys it into a queued estatus entry. Merge __process_error()s work into _in_nmi_notify_one() so that the queued estatus entry is used from the beginning. Use the ghes_peek_estatus() so we know how much memory to allocate from the ghes_estatus_pool before we read the records. Reported-by: Borislav Petkov <bp@xxxxxxx> Signed-off-by: James Morse <james.morse@xxxxxxx> --- drivers/acpi/apei/ghes.c | 45 ++++++++++++++++++++-------------------- 1 file changed, 22 insertions(+), 23 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 055176ed68ac..a0c10b60ad44 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -722,40 +722,32 @@ static void ghes_print_queued_estatus(void) } } -/* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes, - struct acpi_hest_generic_status *ghes_estatus) +static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) { + u64 buf_paddr; + int sev, rc = 0; u32 len, node_len; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic_status *estatus; - if (ghes_estatus_cached(ghes_estatus)) - return; + rc = ghes_peek_estatus(ghes, fixmap_idx, &buf_paddr, &len); + if (rc) + return rc; - len = cper_estatus_len(ghes_estatus); node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); if (!estatus_node) - return; + return -ENOMEM; estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, ghes_estatus, len); - llist_add(&estatus_node->llnode, &ghes_estatus_llist); -} - -static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) -{ - int sev; - u64 buf_paddr; - struct acpi_hest_generic_status *estatus = ghes->estatus; - if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + if (__ghes_read_estatus(estatus, buf_paddr, len, fixmap_idx)) { ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); - return -ENOENT; + rc = -ENOENT; + goto no_work; } sev = ghes_severity(estatus->error_severity); @@ -764,13 +756,20 @@ static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) __ghes_panic(ghes, estatus); } - if (!buf_paddr) - return 0; - - __process_error(ghes, estatus); ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); - return 0; + if (!buf_paddr || ghes_estatus_cached(estatus)) + goto no_work; + + llist_add(&estatus_node->llnode, &ghes_estatus_llist); + + return rc; + +no_work: + gen_pool_free(ghes_estatus_pool, (unsigned long)estatus_node, + node_len); + + return rc; } static int ghes_estatus_queue_notified(struct list_head *rcu_list, -- 2.19.0 _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm