From mboxrd@z Thu Jan 1 00:00:00 1970 From: James Morse Subject: [PATCH v7 17/25] ACPI / APEI: Pass ghes and estatus separately to avoid a later copy Date: Mon, 3 Dec 2018 18:06:05 +0000 Message-ID: <20181203180613.228133-18-james.morse@arm.com> References: <20181203180613.228133-1-james.morse@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20181203180613.228133-1-james.morse@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: linux-acpi@vger.kernel.org Cc: Rafael Wysocki , Tony Luck , Fan Wu , Marc Zyngier , Catalin Marinas , Will Deacon , Dongjiu Geng , linux-mm@kvack.org, Borislav Petkov , Naoya Horiguchi , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Len Brown List-Id: linux-acpi@vger.kernel.org The NMI-like notifications scribble over ghes->estatus, before copying it somewhere else. If this interrupts the ghes_probe() code calling ghes_proc() on each struct ghes, the data is corrupted. All the NMI-like notifications should use a queued estatus entry from the beginning, instead of the ghes version, then copying it. To do this, break up any use of "ghes->estatus" so that all functions take the estatus as an argument. This patch just moves these ghes->estatus dereferences into separate arguments, no change in behaviour. struct ghes becomes unused in ghes_clear_estatus() as it only wanted ghes->estatus, which we now pass directly. This is removed. Signed-off-by: James Morse --- Changes since v6: * Changed subject * Renamed ghes_estatus to src_estatus, which is a little clearer * Removed struct ghes from ghes_clear_estatus() now that this becomes unused in this patch. * Mangled the commit message to be different --- drivers/acpi/apei/ghes.c | 84 +++++++++++++++++++++------------------- 1 file changed, 45 insertions(+), 39 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index b5c31f65a1c0..b70f5fd962cc 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -277,8 +277,9 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, } } -static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) - +static int ghes_read_estatus(struct ghes *ghes, + struct acpi_hest_generic_status *estatus, + u64 *buf_paddr, int fixmap_idx) { struct acpi_hest_generic *g = ghes->generic; u32 len; @@ -295,25 +296,25 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) if (!*buf_paddr) return -ENOENT; - ghes_copy_tofrom_phys(ghes->estatus, *buf_paddr, - sizeof(*ghes->estatus), 1, fixmap_idx); - if (!ghes->estatus->block_status) { + ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1, + fixmap_idx); + if (!estatus->block_status) { *buf_paddr = 0; return -ENOENT; } rc = -EIO; - len = cper_estatus_len(ghes->estatus); - if (len < sizeof(*ghes->estatus)) + len = cper_estatus_len(estatus); + if (len < sizeof(*estatus)) goto err_read_block; if (len > ghes->generic->error_block_length) goto err_read_block; - if (cper_estatus_check_header(ghes->estatus)) + if (cper_estatus_check_header(estatus)) goto err_read_block; - ghes_copy_tofrom_phys(ghes->estatus + 1, - *buf_paddr + sizeof(*ghes->estatus), - len - sizeof(*ghes->estatus), 1, fixmap_idx); - if (cper_estatus_check(ghes->estatus)) + ghes_copy_tofrom_phys(estatus + 1, + *buf_paddr + sizeof(*estatus), + len - sizeof(*estatus), 1, fixmap_idx); + if (cper_estatus_check(estatus)) goto err_read_block; rc = 0; @@ -325,12 +326,13 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) return rc; } -static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr, int fixmap_idx) +static void ghes_clear_estatus(struct acpi_hest_generic_status *estatus, + u64 buf_paddr, int fixmap_idx) { - ghes->estatus->block_status = 0; + estatus->block_status = 0; if (buf_paddr) - ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, - sizeof(ghes->estatus->block_status), 0, + ghes_copy_tofrom_phys(estatus, buf_paddr, + sizeof(estatus->block_status), 0, fixmap_idx); } @@ -638,9 +640,10 @@ static int ghes_ack_error(struct acpi_hest_generic_v2 *gv2) return apei_write(val, &gv2->read_ack_register); } -static void __ghes_panic(struct ghes *ghes) +static void __ghes_panic(struct ghes *ghes, + struct acpi_hest_generic_status *estatus) { - __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); + __ghes_print_estatus(KERN_EMERG, ghes->generic, estatus); /* reboot to log the error! */ if (!panic_timeout) @@ -650,25 +653,25 @@ static void __ghes_panic(struct ghes *ghes) static int ghes_proc(struct ghes *ghes) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int rc; - rc = ghes_read_estatus(ghes, &buf_paddr, FIX_APEI_GHES_IRQ); + rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ); if (rc) goto out; - if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) { - __ghes_panic(ghes); - } + if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC) + __ghes_panic(ghes, estatus); - if (!ghes_estatus_cached(ghes->estatus)) { - if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) - ghes_estatus_cache_add(ghes->generic, ghes->estatus); + if (!ghes_estatus_cached(estatus)) { + if (ghes_print_estatus(NULL, ghes->generic, estatus)) + ghes_estatus_cache_add(ghes->generic, estatus); } - ghes_do_proc(ghes, ghes->estatus); + ghes_do_proc(ghes, estatus); out: - ghes_clear_estatus(ghes, buf_paddr, FIX_APEI_GHES_IRQ); + ghes_clear_estatus(estatus, buf_paddr, FIX_APEI_GHES_IRQ); if (rc == -ENOENT) return rc; @@ -819,17 +822,20 @@ static void ghes_print_queued_estatus(void) } /* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes) +static void __process_error(struct ghes *ghes, + struct acpi_hest_generic_status *src_estatus) { -#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG u32 len, node_len; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic_status *estatus; - if (ghes_estatus_cached(ghes->estatus)) + if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG)) return; - len = cper_estatus_len(ghes->estatus); + if (ghes_estatus_cached(src_estatus)) + return; + + len = cper_estatus_len(src_estatus); node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); @@ -839,29 +845,29 @@ static void __process_error(struct ghes *ghes) estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, ghes->estatus, len); + memcpy(estatus, src_estatus, len); llist_add(&estatus_node->llnode, &ghes_estatus_llist); -#endif } static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int sev; - if (ghes_read_estatus(ghes, &buf_paddr, fixmap_idx)) { - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); return -ENOENT; } - sev = ghes_severity(ghes->estatus->error_severity); + sev = ghes_severity(estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); - __ghes_panic(ghes); + __ghes_panic(ghes, estatus); } - __process_error(ghes); - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + __process_error(ghes, estatus); + ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); if (is_hest_type_generic_v2(ghes) && ghes_ack_error(ghes->generic_v2)) pr_warn_ratelimited(FW_WARN GHES_PFX -- 2.19.2 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ot1-f69.google.com (mail-ot1-f69.google.com [209.85.210.69]) by kanga.kvack.org (Postfix) with ESMTP id 6CF156B6A87 for ; Mon, 3 Dec 2018 13:07:39 -0500 (EST) Received: by mail-ot1-f69.google.com with SMTP id d5so3847689otl.21 for ; Mon, 03 Dec 2018 10:07:39 -0800 (PST) Received: from foss.arm.com (usa-sjc-mx-foss1.foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id y203si5763511oie.110.2018.12.03.10.07.38 for ; Mon, 03 Dec 2018 10:07:38 -0800 (PST) From: James Morse Subject: [PATCH v7 17/25] ACPI / APEI: Pass ghes and estatus separately to avoid a later copy Date: Mon, 3 Dec 2018 18:06:05 +0000 Message-Id: <20181203180613.228133-18-james.morse@arm.com> In-Reply-To: <20181203180613.228133-1-james.morse@arm.com> References: <20181203180613.228133-1-james.morse@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: linux-acpi@vger.kernel.org Cc: kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, Borislav Petkov , Marc Zyngier , Christoffer Dall , Will Deacon , Catalin Marinas , Naoya Horiguchi , Rafael Wysocki , Len Brown , Tony Luck , Dongjiu Geng , Xie XiuQi , Fan Wu , James Morse The NMI-like notifications scribble over ghes->estatus, before copying it somewhere else. If this interrupts the ghes_probe() code calling ghes_proc() on each struct ghes, the data is corrupted. All the NMI-like notifications should use a queued estatus entry from the beginning, instead of the ghes version, then copying it. To do this, break up any use of "ghes->estatus" so that all functions take the estatus as an argument. This patch just moves these ghes->estatus dereferences into separate arguments, no change in behaviour. struct ghes becomes unused in ghes_clear_estatus() as it only wanted ghes->estatus, which we now pass directly. This is removed. Signed-off-by: James Morse --- Changes since v6: * Changed subject * Renamed ghes_estatus to src_estatus, which is a little clearer * Removed struct ghes from ghes_clear_estatus() now that this becomes unused in this patch. * Mangled the commit message to be different --- drivers/acpi/apei/ghes.c | 84 +++++++++++++++++++++------------------- 1 file changed, 45 insertions(+), 39 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index b5c31f65a1c0..b70f5fd962cc 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -277,8 +277,9 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, } } -static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) - +static int ghes_read_estatus(struct ghes *ghes, + struct acpi_hest_generic_status *estatus, + u64 *buf_paddr, int fixmap_idx) { struct acpi_hest_generic *g = ghes->generic; u32 len; @@ -295,25 +296,25 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) if (!*buf_paddr) return -ENOENT; - ghes_copy_tofrom_phys(ghes->estatus, *buf_paddr, - sizeof(*ghes->estatus), 1, fixmap_idx); - if (!ghes->estatus->block_status) { + ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1, + fixmap_idx); + if (!estatus->block_status) { *buf_paddr = 0; return -ENOENT; } rc = -EIO; - len = cper_estatus_len(ghes->estatus); - if (len < sizeof(*ghes->estatus)) + len = cper_estatus_len(estatus); + if (len < sizeof(*estatus)) goto err_read_block; if (len > ghes->generic->error_block_length) goto err_read_block; - if (cper_estatus_check_header(ghes->estatus)) + if (cper_estatus_check_header(estatus)) goto err_read_block; - ghes_copy_tofrom_phys(ghes->estatus + 1, - *buf_paddr + sizeof(*ghes->estatus), - len - sizeof(*ghes->estatus), 1, fixmap_idx); - if (cper_estatus_check(ghes->estatus)) + ghes_copy_tofrom_phys(estatus + 1, + *buf_paddr + sizeof(*estatus), + len - sizeof(*estatus), 1, fixmap_idx); + if (cper_estatus_check(estatus)) goto err_read_block; rc = 0; @@ -325,12 +326,13 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) return rc; } -static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr, int fixmap_idx) +static void ghes_clear_estatus(struct acpi_hest_generic_status *estatus, + u64 buf_paddr, int fixmap_idx) { - ghes->estatus->block_status = 0; + estatus->block_status = 0; if (buf_paddr) - ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, - sizeof(ghes->estatus->block_status), 0, + ghes_copy_tofrom_phys(estatus, buf_paddr, + sizeof(estatus->block_status), 0, fixmap_idx); } @@ -638,9 +640,10 @@ static int ghes_ack_error(struct acpi_hest_generic_v2 *gv2) return apei_write(val, &gv2->read_ack_register); } -static void __ghes_panic(struct ghes *ghes) +static void __ghes_panic(struct ghes *ghes, + struct acpi_hest_generic_status *estatus) { - __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); + __ghes_print_estatus(KERN_EMERG, ghes->generic, estatus); /* reboot to log the error! */ if (!panic_timeout) @@ -650,25 +653,25 @@ static void __ghes_panic(struct ghes *ghes) static int ghes_proc(struct ghes *ghes) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int rc; - rc = ghes_read_estatus(ghes, &buf_paddr, FIX_APEI_GHES_IRQ); + rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ); if (rc) goto out; - if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) { - __ghes_panic(ghes); - } + if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC) + __ghes_panic(ghes, estatus); - if (!ghes_estatus_cached(ghes->estatus)) { - if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) - ghes_estatus_cache_add(ghes->generic, ghes->estatus); + if (!ghes_estatus_cached(estatus)) { + if (ghes_print_estatus(NULL, ghes->generic, estatus)) + ghes_estatus_cache_add(ghes->generic, estatus); } - ghes_do_proc(ghes, ghes->estatus); + ghes_do_proc(ghes, estatus); out: - ghes_clear_estatus(ghes, buf_paddr, FIX_APEI_GHES_IRQ); + ghes_clear_estatus(estatus, buf_paddr, FIX_APEI_GHES_IRQ); if (rc == -ENOENT) return rc; @@ -819,17 +822,20 @@ static void ghes_print_queued_estatus(void) } /* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes) +static void __process_error(struct ghes *ghes, + struct acpi_hest_generic_status *src_estatus) { -#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG u32 len, node_len; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic_status *estatus; - if (ghes_estatus_cached(ghes->estatus)) + if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG)) return; - len = cper_estatus_len(ghes->estatus); + if (ghes_estatus_cached(src_estatus)) + return; + + len = cper_estatus_len(src_estatus); node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); @@ -839,29 +845,29 @@ static void __process_error(struct ghes *ghes) estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, ghes->estatus, len); + memcpy(estatus, src_estatus, len); llist_add(&estatus_node->llnode, &ghes_estatus_llist); -#endif } static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int sev; - if (ghes_read_estatus(ghes, &buf_paddr, fixmap_idx)) { - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); return -ENOENT; } - sev = ghes_severity(ghes->estatus->error_severity); + sev = ghes_severity(estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); - __ghes_panic(ghes); + __ghes_panic(ghes, estatus); } - __process_error(ghes); - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + __process_error(ghes, estatus); + ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); if (is_hest_type_generic_v2(ghes) && ghes_ack_error(ghes->generic_v2)) pr_warn_ratelimited(FW_WARN GHES_PFX -- 2.19.2 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 09599C04EB9 for ; 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Mon, 03 Dec 2018 18:07:52 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D35571993; Mon, 3 Dec 2018 10:07:37 -0800 (PST) Received: from eglon.cambridge.arm.com (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 0F40A3F59C; Mon, 3 Dec 2018 10:07:34 -0800 (PST) From: James Morse To: linux-acpi@vger.kernel.org Subject: [PATCH v7 17/25] ACPI / APEI: Pass ghes and estatus separately to avoid a later copy Date: Mon, 3 Dec 2018 18:06:05 +0000 Message-Id: <20181203180613.228133-18-james.morse@arm.com> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181203180613.228133-1-james.morse@arm.com> References: <20181203180613.228133-1-james.morse@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20181203_180751_022076_0D634CA9 X-CRM114-Status: GOOD ( 18.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Rafael Wysocki , Tony Luck , Fan Wu , Xie XiuQi , Marc Zyngier , Catalin Marinas , Will Deacon , Christoffer Dall , Dongjiu Geng , linux-mm@kvack.org, Borislav Petkov , James Morse , Naoya Horiguchi , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, Len Brown Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org The NMI-like notifications scribble over ghes->estatus, before copying it somewhere else. If this interrupts the ghes_probe() code calling ghes_proc() on each struct ghes, the data is corrupted. All the NMI-like notifications should use a queued estatus entry from the beginning, instead of the ghes version, then copying it. To do this, break up any use of "ghes->estatus" so that all functions take the estatus as an argument. This patch just moves these ghes->estatus dereferences into separate arguments, no change in behaviour. struct ghes becomes unused in ghes_clear_estatus() as it only wanted ghes->estatus, which we now pass directly. This is removed. Signed-off-by: James Morse --- Changes since v6: * Changed subject * Renamed ghes_estatus to src_estatus, which is a little clearer * Removed struct ghes from ghes_clear_estatus() now that this becomes unused in this patch. * Mangled the commit message to be different --- drivers/acpi/apei/ghes.c | 84 +++++++++++++++++++++------------------- 1 file changed, 45 insertions(+), 39 deletions(-) diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c index b5c31f65a1c0..b70f5fd962cc 100644 --- a/drivers/acpi/apei/ghes.c +++ b/drivers/acpi/apei/ghes.c @@ -277,8 +277,9 @@ static void ghes_copy_tofrom_phys(void *buffer, u64 paddr, u32 len, } } -static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) - +static int ghes_read_estatus(struct ghes *ghes, + struct acpi_hest_generic_status *estatus, + u64 *buf_paddr, int fixmap_idx) { struct acpi_hest_generic *g = ghes->generic; u32 len; @@ -295,25 +296,25 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) if (!*buf_paddr) return -ENOENT; - ghes_copy_tofrom_phys(ghes->estatus, *buf_paddr, - sizeof(*ghes->estatus), 1, fixmap_idx); - if (!ghes->estatus->block_status) { + ghes_copy_tofrom_phys(estatus, *buf_paddr, sizeof(*estatus), 1, + fixmap_idx); + if (!estatus->block_status) { *buf_paddr = 0; return -ENOENT; } rc = -EIO; - len = cper_estatus_len(ghes->estatus); - if (len < sizeof(*ghes->estatus)) + len = cper_estatus_len(estatus); + if (len < sizeof(*estatus)) goto err_read_block; if (len > ghes->generic->error_block_length) goto err_read_block; - if (cper_estatus_check_header(ghes->estatus)) + if (cper_estatus_check_header(estatus)) goto err_read_block; - ghes_copy_tofrom_phys(ghes->estatus + 1, - *buf_paddr + sizeof(*ghes->estatus), - len - sizeof(*ghes->estatus), 1, fixmap_idx); - if (cper_estatus_check(ghes->estatus)) + ghes_copy_tofrom_phys(estatus + 1, + *buf_paddr + sizeof(*estatus), + len - sizeof(*estatus), 1, fixmap_idx); + if (cper_estatus_check(estatus)) goto err_read_block; rc = 0; @@ -325,12 +326,13 @@ static int ghes_read_estatus(struct ghes *ghes, u64 *buf_paddr, int fixmap_idx) return rc; } -static void ghes_clear_estatus(struct ghes *ghes, u64 buf_paddr, int fixmap_idx) +static void ghes_clear_estatus(struct acpi_hest_generic_status *estatus, + u64 buf_paddr, int fixmap_idx) { - ghes->estatus->block_status = 0; + estatus->block_status = 0; if (buf_paddr) - ghes_copy_tofrom_phys(ghes->estatus, buf_paddr, - sizeof(ghes->estatus->block_status), 0, + ghes_copy_tofrom_phys(estatus, buf_paddr, + sizeof(estatus->block_status), 0, fixmap_idx); } @@ -638,9 +640,10 @@ static int ghes_ack_error(struct acpi_hest_generic_v2 *gv2) return apei_write(val, &gv2->read_ack_register); } -static void __ghes_panic(struct ghes *ghes) +static void __ghes_panic(struct ghes *ghes, + struct acpi_hest_generic_status *estatus) { - __ghes_print_estatus(KERN_EMERG, ghes->generic, ghes->estatus); + __ghes_print_estatus(KERN_EMERG, ghes->generic, estatus); /* reboot to log the error! */ if (!panic_timeout) @@ -650,25 +653,25 @@ static void __ghes_panic(struct ghes *ghes) static int ghes_proc(struct ghes *ghes) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int rc; - rc = ghes_read_estatus(ghes, &buf_paddr, FIX_APEI_GHES_IRQ); + rc = ghes_read_estatus(ghes, estatus, &buf_paddr, FIX_APEI_GHES_IRQ); if (rc) goto out; - if (ghes_severity(ghes->estatus->error_severity) >= GHES_SEV_PANIC) { - __ghes_panic(ghes); - } + if (ghes_severity(estatus->error_severity) >= GHES_SEV_PANIC) + __ghes_panic(ghes, estatus); - if (!ghes_estatus_cached(ghes->estatus)) { - if (ghes_print_estatus(NULL, ghes->generic, ghes->estatus)) - ghes_estatus_cache_add(ghes->generic, ghes->estatus); + if (!ghes_estatus_cached(estatus)) { + if (ghes_print_estatus(NULL, ghes->generic, estatus)) + ghes_estatus_cache_add(ghes->generic, estatus); } - ghes_do_proc(ghes, ghes->estatus); + ghes_do_proc(ghes, estatus); out: - ghes_clear_estatus(ghes, buf_paddr, FIX_APEI_GHES_IRQ); + ghes_clear_estatus(estatus, buf_paddr, FIX_APEI_GHES_IRQ); if (rc == -ENOENT) return rc; @@ -819,17 +822,20 @@ static void ghes_print_queued_estatus(void) } /* Save estatus for further processing in IRQ context */ -static void __process_error(struct ghes *ghes) +static void __process_error(struct ghes *ghes, + struct acpi_hest_generic_status *src_estatus) { -#ifdef CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG u32 len, node_len; struct ghes_estatus_node *estatus_node; struct acpi_hest_generic_status *estatus; - if (ghes_estatus_cached(ghes->estatus)) + if (!IS_ENABLED(CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG)) return; - len = cper_estatus_len(ghes->estatus); + if (ghes_estatus_cached(src_estatus)) + return; + + len = cper_estatus_len(src_estatus); node_len = GHES_ESTATUS_NODE_LEN(len); estatus_node = (void *)gen_pool_alloc(ghes_estatus_pool, node_len); @@ -839,29 +845,29 @@ static void __process_error(struct ghes *ghes) estatus_node->ghes = ghes; estatus_node->generic = ghes->generic; estatus = GHES_ESTATUS_FROM_NODE(estatus_node); - memcpy(estatus, ghes->estatus, len); + memcpy(estatus, src_estatus, len); llist_add(&estatus_node->llnode, &ghes_estatus_llist); -#endif } static int _in_nmi_notify_one(struct ghes *ghes, int fixmap_idx) { + struct acpi_hest_generic_status *estatus = ghes->estatus; u64 buf_paddr; int sev; - if (ghes_read_estatus(ghes, &buf_paddr, fixmap_idx)) { - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + if (ghes_read_estatus(ghes, estatus, &buf_paddr, fixmap_idx)) { + ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); return -ENOENT; } - sev = ghes_severity(ghes->estatus->error_severity); + sev = ghes_severity(estatus->error_severity); if (sev >= GHES_SEV_PANIC) { ghes_print_queued_estatus(); - __ghes_panic(ghes); + __ghes_panic(ghes, estatus); } - __process_error(ghes); - ghes_clear_estatus(ghes, buf_paddr, fixmap_idx); + __process_error(ghes, estatus); + ghes_clear_estatus(estatus, buf_paddr, fixmap_idx); if (is_hest_type_generic_v2(ghes) && ghes_ack_error(ghes->generic_v2)) pr_warn_ratelimited(FW_WARN GHES_PFX -- 2.19.2 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel