From d9f608dc156487b55cb17c2ec591b06e53a6de64 Mon Sep 17 00:00:00 2001 From: James Morse Date: Tue, 29 Jan 2019 18:48:56 +0000 Subject: ACPI / APEI: Only use queued estatus entry during in_nmi_queue_one_entry() 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_queue_one_entry() to stage the estatus data, before __process_error() copys it into a queued estatus entry. Merge __process_error()s work into in_nmi_queue_one_entry() so that the queued estatus entry is used from the beginning. Use the new ghes_peek_estatus() to know how much memory to allocate from the ghes_estatus_pool before reading the records. Reported-by: Borislav Petkov Signed-off-by: James Morse Reviewed-by: Borislav Petkov Change since v6: * Added a comment explaining the 'ack-error, then goto no_work'. * Added missing esatus-clearing, which is necessary after reading the GAS, Signed-off-by: Rafael J. Wysocki --- drivers/acpi/apei/ghes.c | 64 ++++++++++++++++++++++++++++-------------------- 1 file changed, 37 insertions(+), 27 deletions(-) (limited to 'drivers/acpi') diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index 4c1d8e5e9ada..eb5bf2ced1fb 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -862,57 +862,67 @@ 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 *src_estatus) +static int ghes_in_nmi_queue_one_entry(struct ghes *ghes, + enum fixed_addresses fixmap_idx) { - u32 len, node_len; + struct acpi_hest_generic_status *estatus, tmp_header; struct ghes_estatus_node *estatus_node; - struct acpi_hest_generic_status *estatus; + u32 len, node_len; + u64 buf_paddr; + int sev, rc; if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG)) - return; + return -EOPNOTSUPP; - if (ghes_estatus_cached(src_estatus)) - return; + rc = __ghes_peek_estatus(ghes, &tmp_header, &buf_paddr, fixmap_idx); + if (rc) { + ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx); + return rc; + } - len = cper_estatus_len(src_estatus); - node_len = GHES_ESTATUS_NODE_LEN(len); + rc = __ghes_check_estatus(ghes, &tmp_header); + if (rc) { + ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx); + return rc; + } + len = cper_estatus_len(&tmp_header); + 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, src_estatus, len); - llist_add(&estatus_node->llnode, &ghes_estatus_llist); -} -static int ghes_in_nmi_queue_one_entry(struct ghes *ghes, - enum fixed_addresses fixmap_idx) -{ - struct acpi_hest_generic_status *estatus = ghes->estatus; - u64 buf_paddr; - int sev; - - if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + if (__ghes_read_estatus(estatus, buf_paddr, fixmap_idx, len)) { ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); - return -ENOENT; + rc = -ENOENT; + goto no_work; } sev = ghes_severity(estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); __ghes_panic(ghes, estatus, buf_paddr, fixmap_idx); - } - __process_error(ghes, estatus); - ghes_clear_estatus(ghes, estatus, buf_paddr, fixmap_idx); + ghes_clear_estatus(ghes, &tmp_header, buf_paddr, fixmap_idx); - return 0; + /* This error has been reported before, don't process it again. */ + if (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_in_nmi_spool_from_list(struct list_head *rcu_list, -- cgit