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Date: Fri, 15 May 2009 14:22:30 +0200
From: Borislav Petkov <borislav.petkov@....com>
To: <akpm@...ux-foundation.org>, <greg@...ah.com>, <mingo@...e.hu>
Cc: <norsk5@...oo.com>, <tglx@...utronix.de>, <hpa@...or.com>,
<mchehab@...hat.com>, <aris@...hat.com>, edt@....ca,
<linux-kernel@...r.kernel.org>,
Doug Thompson <dougthompson@...ssion.com>,
Borislav Petkov <borislav.petkov@....com>
Subject: [PATCH 19/22] amd64_edac: add error decoding logic
From: Doug Thompson <dougthompson@...ssion.com>
Borislav:
- fold amd64_error_info_valid() into its only user
- fix/cleanup comments
- fix function return value patterns
- cleanup debug calls
Reviewed-by: Mauro Carvalho Chehab <mchehab@...hat.com>
Signed-off-by: Doug Thompson <dougthompson@...ssion.com>
Signed-off-by: Borislav Petkov <borislav.petkov@....com>
---
drivers/edac/amd64_edac.c | 425 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 425 insertions(+), 0 deletions(-)
diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 68b5892..2807c97 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -2030,3 +2030,428 @@ static int get_channel_from_ecc_syndrome(unsigned short syndrome)
debugf0("syndrome(%x) not found\n", syndrome);
return -1;
}
+
+/*
+ * Check for valid error in the NB Status High register. If so, proceed to read
+ * NB Status Low, NB Address Low and NB Address High registers and store data
+ * into error structure.
+ *
+ * Returns:
+ * - 1: if hardware regs contains valid error info
+ * - 0: if no valid error is indicated
+ */
+static int amd64_get_error_info_regs(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *regs)
+{
+ struct amd64_pvt *pvt;
+ struct pci_dev *misc_f3_ctl;
+ int err = 0;
+
+ pvt = mci->pvt_info;
+ misc_f3_ctl = pvt->misc_f3_ctl;
+
+ err = pci_read_config_dword(misc_f3_ctl, K8_NBSH, ®s->nbsh);
+ if (err)
+ goto err_reg;
+
+ if (!(regs->nbsh & K8_NBSH_VALID_BIT))
+ return 0;
+
+ /* valid error, read remaining error information registers */
+ err = pci_read_config_dword(misc_f3_ctl, K8_NBSL, ®s->nbsl);
+ if (err)
+ goto err_reg;
+
+ err = pci_read_config_dword(misc_f3_ctl, K8_NBEAL, ®s->nbeal);
+ if (err)
+ goto err_reg;
+
+ err = pci_read_config_dword(misc_f3_ctl, K8_NBEAH, ®s->nbeah);
+ if (err)
+ goto err_reg;
+
+ err = pci_read_config_dword(misc_f3_ctl, K8_NBCFG, ®s->nbcfg);
+ if (err)
+ goto err_reg;
+
+ return 1;
+
+err_reg:
+ debugf0("Reading error info register failed\n");
+ return 0;
+}
+
+/*
+ * This function is called to retrieve the error data from hardware and store it
+ * in the info structure.
+ *
+ * Returns:
+ * - 1: if a valid error is found
+ * - 0: if no error is found
+ */
+static int amd64_get_error_info(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info)
+{
+ struct amd64_pvt *pvt;
+ struct amd64_error_info_regs regs;
+
+ pvt = mci->pvt_info;
+
+ if (!amd64_get_error_info_regs(mci, info))
+ return 0;
+
+ /*
+ * Here's the problem with the K8's EDAC reporting: There are four
+ * registers which report pieces of error information. They are shared
+ * between CEs and UEs. Furthermore, contrary to what is stated in the
+ * BKDG, the overflow bit is never used! Every error always updates the
+ * reporting registers.
+ *
+ * Can you see the race condition? All four error reporting registers
+ * must be read before a new error updates them! There is no way to read
+ * all four registers atomically. The best than can be done is to detect
+ * that a race has occured and then report the error without any kind of
+ * precision.
+ *
+ * What is still positive is that errors are still reported and thus
+ * problems can still be detected - just not localized because the
+ * syndrome and address are spread out across registers.
+ *
+ * Grrrrr!!!!! Here's hoping that AMD fixes this in some future K8 rev.
+ * UEs and CEs should have separate register sets with proper overflow
+ * bits that are used! At very least the problem can be fixed by
+ * honoring the ErrValid bit in 'nbsh' and not updating registers - just
+ * set the overflow bit - unless the current error is CE and the new
+ * error is UE which would be the only situation for overwriting the
+ * current values.
+ */
+
+ regs = *info;
+
+ /* Use info from the second read - most current */
+ if (unlikely(!amd64_get_error_info_regs(mci, info)))
+ return 0;
+
+ /* clear the error bits in hardware */
+ pci_write_bits32(pvt->misc_f3_ctl, K8_NBSH, 0, K8_NBSH_VALID_BIT);
+
+ /* Check for the possible race condition */
+ if ((regs.nbsh != info->nbsh) ||
+ (regs.nbsl != info->nbsl) ||
+ (regs.nbeah != info->nbeah) ||
+ (regs.nbeal != info->nbeal)) {
+ amd64_mc_printk(mci, KERN_WARNING,
+ "hardware STATUS read access race condition "
+ "detected!\n");
+ return 0;
+ }
+ return 1;
+}
+
+static inline void amd64_decode_gart_tlb_error(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info)
+{
+ u32 err_code;
+ u32 ec_tt; /* error code transaction type (2b) */
+ u32 ec_ll; /* error code cache level (2b) */
+
+ err_code = EXTRACT_ERROR_CODE(info->nbsl);
+ ec_ll = EXTRACT_LL_CODE(err_code);
+ ec_tt = EXTRACT_TT_CODE(err_code);
+
+ amd64_mc_printk(mci, KERN_ERR,
+ "GART TLB event: transaction type(%s), "
+ "cache level(%s)\n", tt_msgs[ec_tt], ll_msgs[ec_ll]);
+}
+
+static inline void amd64_decode_mem_cache_error(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info)
+{
+ u32 err_code;
+ u32 ec_rrrr; /* error code memory transaction (4b) */
+ u32 ec_tt; /* error code transaction type (2b) */
+ u32 ec_ll; /* error code cache level (2b) */
+
+ err_code = EXTRACT_ERROR_CODE(info->nbsl);
+ ec_ll = EXTRACT_LL_CODE(err_code);
+ ec_tt = EXTRACT_TT_CODE(err_code);
+ ec_rrrr = EXTRACT_RRRR_CODE(err_code);
+
+ amd64_mc_printk(mci, KERN_ERR,
+ "cache hierarchy error: memory transaction type(%s), "
+ "transaction type(%s), cache level(%s)\n",
+ rrrr_msgs[ec_rrrr], tt_msgs[ec_tt], ll_msgs[ec_ll]);
+}
+
+
+/*
+ * Handle any Correctable Errors (CEs) that have occurred. Check for valid ERROR
+ * ADDRESS and process.
+ */
+static void amd64_handle_ce(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info)
+{
+ struct amd64_pvt *pvt = mci->pvt_info;
+ u64 SystemAddress;
+
+ /* Ensure that the Error Address is VALID */
+ if ((info->nbsh & K8_NBSH_VALID_ERROR_ADDR) == 0) {
+ amd64_mc_printk(mci, KERN_ERR,
+ "HW has no ERROR_ADDRESS available\n");
+ edac_mc_handle_ce_no_info(mci, EDAC_MOD_STR);
+ return;
+ }
+
+ SystemAddress = extract_error_address(mci, info);
+
+ amd64_mc_printk(mci, KERN_ERR,
+ "CE ERROR_ADDRESS= 0x%llx\n", SystemAddress);
+
+ pvt->ops->map_sysaddr_to_csrow(mci, info, SystemAddress);
+}
+
+/* Handle any Un-correctable Errors (UEs) */
+static void amd64_handle_ue(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info)
+{
+ int csrow;
+ u64 SystemAddress;
+ u32 page, offset;
+ struct mem_ctl_info *log_mci, *src_mci = NULL;
+
+ log_mci = mci;
+
+ if ((info->nbsh & K8_NBSH_VALID_ERROR_ADDR) == 0) {
+ amd64_mc_printk(mci, KERN_CRIT,
+ "HW has no ERROR_ADDRESS available\n");
+ edac_mc_handle_ue_no_info(log_mci, EDAC_MOD_STR);
+ return;
+ }
+
+ SystemAddress = extract_error_address(mci, info);
+
+ /*
+ * Find out which node the error address belongs to. This may be
+ * different from the node that detected the error.
+ */
+ src_mci = find_mc_by_sys_addr(mci, SystemAddress);
+ if (!src_mci) {
+ amd64_mc_printk(mci, KERN_CRIT,
+ "ERROR ADDRESS (0x%lx) value NOT mapped to a MC\n",
+ (unsigned long)SystemAddress);
+ edac_mc_handle_ue_no_info(log_mci, EDAC_MOD_STR);
+ return;
+ }
+
+ log_mci = src_mci;
+
+ csrow = sys_addr_to_csrow(log_mci, SystemAddress);
+ if (csrow < 0) {
+ amd64_mc_printk(mci, KERN_CRIT,
+ "ERROR_ADDRESS (0x%lx) value NOT mapped to 'csrow'\n",
+ (unsigned long)SystemAddress);
+ edac_mc_handle_ue_no_info(log_mci, EDAC_MOD_STR);
+ } else {
+ error_address_to_page_and_offset(SystemAddress, &page, &offset);
+ edac_mc_handle_ue(log_mci, page, offset, csrow, EDAC_MOD_STR);
+ }
+}
+
+static void amd64_decode_bus_error(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info)
+{
+ u32 err_code, ext_ec;
+ u32 ec_pp; /* error code participating processor (2p) */
+ u32 ec_to; /* error code timed out (1b) */
+ u32 ec_rrrr; /* error code memory transaction (4b) */
+ u32 ec_ii; /* error code memory or I/O (2b) */
+ u32 ec_ll; /* error code cache level (2b) */
+
+ ext_ec = EXTRACT_EXT_ERROR_CODE(info->nbsl);
+ err_code = EXTRACT_ERROR_CODE(info->nbsl);
+
+ ec_ll = EXTRACT_LL_CODE(err_code);
+ ec_ii = EXTRACT_II_CODE(err_code);
+ ec_rrrr = EXTRACT_RRRR_CODE(err_code);
+ ec_to = EXTRACT_TO_CODE(err_code);
+ ec_pp = EXTRACT_PP_CODE(err_code);
+
+ amd64_mc_printk(mci, KERN_ERR,
+ "BUS ERROR:\n"
+ " time-out(%s) mem or i/o(%s)\n"
+ " participating processor(%s)\n"
+ " memory transaction type(%s)\n"
+ " cache level(%s) Error Found by: %s\n",
+ to_msgs[ec_to],
+ ii_msgs[ec_ii],
+ pp_msgs[ec_pp],
+ rrrr_msgs[ec_rrrr],
+ ll_msgs[ec_ll],
+ (info->nbsh & K8_NBSH_ERR_SCRUBER) ?
+ "Scrubber" : "Normal Operation");
+
+ /* If this was an 'observed' error, early out */
+ if (ec_pp == K8_NBSL_PP_OBS)
+ return; /* We aren't the node involved */
+
+ /* Parse out the extended error code for ECC events */
+ switch (ext_ec) {
+ /* F10 changed to one Extended ECC error code */
+ case F10_NBSL_EXT_ERR_RES: /* Reserved field */
+ case F10_NBSL_EXT_ERR_ECC: /* F10 ECC ext err code */
+ break;
+
+ default:
+ amd64_mc_printk(mci, KERN_ERR, "NOT ECC: no special error "
+ "handling for this error\n");
+ return;
+ }
+
+ if (info->nbsh & K8_NBSH_CECC)
+ amd64_handle_ce(mci, info);
+ else if (info->nbsh & K8_NBSH_UECC)
+ amd64_handle_ue(mci, info);
+
+ /*
+ * If main error is CE then overflow must be CE. If main error is UE
+ * then overflow is unknown. We'll call the overflow a CE - if
+ * panic_on_ue is set then we're already panic'ed and won't arrive
+ * here. Else, then apparently someone doesn't think that UE's are
+ * catastrophic.
+ */
+ if (info->nbsh & K8_NBSH_OVERFLOW)
+ edac_mc_handle_ce_no_info(mci, EDAC_MOD_STR
+ "Error Overflow set");
+}
+
+int amd64_process_error_info(struct mem_ctl_info *mci,
+ struct amd64_error_info_regs *info,
+ int handle_errors)
+{
+ struct amd64_pvt *pvt;
+ struct amd64_error_info_regs *regs;
+ u32 err_code, ext_ec;
+ int gart_tlb_error = 0;
+
+ pvt = mci->pvt_info;
+
+ /* If caller doesn't want us to process the error, return */
+ if (!handle_errors)
+ return 1;
+
+ regs = info;
+
+ debugf1("NorthBridge ERROR: mci(0x%p)\n", mci);
+ debugf1(" MC node(%d) Error-Address(0x%.8x-%.8x)\n",
+ pvt->mc_node_id, regs->nbeah, regs->nbeal);
+ debugf1(" nbsh(0x%.8x) nbsl(0x%.8x)\n",
+ regs->nbsh, regs->nbsl);
+ debugf1(" Valid Error=%s Overflow=%s\n",
+ (regs->nbsh & K8_NBSH_VALID_BIT) ? "True" : "False",
+ (regs->nbsh & K8_NBSH_OVERFLOW) ? "True" : "False");
+ debugf1(" Err Uncorrected=%s MCA Error Reporting=%s\n",
+ (regs->nbsh & K8_NBSH_UNCORRECTED_ERR) ?
+ "True" : "False",
+ (regs->nbsh & K8_NBSH_ERR_ENABLE) ?
+ "True" : "False");
+ debugf1(" MiscErr Valid=%s ErrAddr Valid=%s PCC=%s\n",
+ (regs->nbsh & K8_NBSH_MISC_ERR_VALID) ?
+ "True" : "False",
+ (regs->nbsh & K8_NBSH_VALID_ERROR_ADDR) ?
+ "True" : "False",
+ (regs->nbsh & K8_NBSH_PCC) ?
+ "True" : "False");
+ debugf1(" CECC=%s UECC=%s Found by Scruber=%s\n",
+ (regs->nbsh & K8_NBSH_CECC) ?
+ "True" : "False",
+ (regs->nbsh & K8_NBSH_UECC) ?
+ "True" : "False",
+ (regs->nbsh & K8_NBSH_ERR_SCRUBER) ?
+ "True" : "False");
+ debugf1(" CORE0=%s CORE1=%s CORE2=%s CORE3=%s\n",
+ (regs->nbsh & K8_NBSH_CORE0) ? "True" : "False",
+ (regs->nbsh & K8_NBSH_CORE1) ? "True" : "False",
+ (regs->nbsh & K8_NBSH_CORE2) ? "True" : "False",
+ (regs->nbsh & K8_NBSH_CORE3) ? "True" : "False");
+
+
+ err_code = EXTRACT_ERROR_CODE(regs->nbsl);
+
+ /* Determine which error type:
+ * 1) GART errors - non-fatal, developmental events
+ * 2) MEMORY errors
+ * 3) BUS errors
+ * 4) Unknown error
+ */
+ if (TEST_TLB_ERROR(err_code)) {
+ /*
+ * GART errors are intended to help graphics driver developers
+ * to detect bad GART PTEs. It is recommended by AMD to disable
+ * GART table walk error reporting by default[1] (currently
+ * being disabled in mce_cpu_quirks()) and according to the
+ * comment in mce_cpu_quirks(), such GART errors can be
+ * incorrectly triggered. We may see these errors anyway and
+ * unless requested by the user, they won't be reported.
+ *
+ * [1] section 13.10.1 on BIOS and Kernel Developers Guide for
+ * AMD NPT family 0Fh processors
+ */
+ if (report_gart_errors == 0)
+ return 1;
+
+ /*
+ * Only if GART error reporting is requested should we generate
+ * any logs.
+ */
+ gart_tlb_error = 1;
+
+ debugf1("GART TLB error\n");
+ amd64_decode_gart_tlb_error(mci, info);
+ } else if (TEST_MEM_ERROR(err_code)) {
+ debugf1("Memory/Cache error\n");
+ amd64_decode_mem_cache_error(mci, info);
+ } else if (TEST_BUS_ERROR(err_code)) {
+ debugf1("Bus (Link/DRAM) error\n");
+ amd64_decode_bus_error(mci, info);
+ } else {
+ /* shouldn't reach here! */
+ amd64_mc_printk(mci, KERN_WARNING,
+ "%s(): unknown MCE error 0x%x\n", __func__,
+ err_code);
+ }
+
+ ext_ec = EXTRACT_EXT_ERROR_CODE(regs->nbsl);
+ amd64_mc_printk(mci, KERN_ERR,
+ "ExtErr=(0x%x) %s\n", ext_ec, ext_msgs[ext_ec]);
+
+ if (((ext_ec >= F10_NBSL_EXT_ERR_CRC &&
+ ext_ec <= F10_NBSL_EXT_ERR_TGT) ||
+ (ext_ec == F10_NBSL_EXT_ERR_RMW)) &&
+ EXTRACT_LDT_LINK(info->nbsh)) {
+
+ amd64_mc_printk(mci, KERN_ERR,
+ "Error on hypertransport link: %s\n",
+ htlink_msgs[
+ EXTRACT_LDT_LINK(info->nbsh)]);
+ }
+
+ /*
+ * Check the UE bit of the NB status high register, if set generate some
+ * logs. If NOT a GART error, then process the event as a NO-INFO event.
+ * If it was a GART error, skip that process.
+ */
+ if (regs->nbsh & K8_NBSH_UNCORRECTED_ERR) {
+ amd64_mc_printk(mci, KERN_CRIT, "uncorrected error\n");
+ if (!gart_tlb_error)
+ edac_mc_handle_ue_no_info(mci, "UE bit is set\n");
+ }
+
+ if (regs->nbsh & K8_NBSH_PCC)
+ amd64_mc_printk(mci, KERN_CRIT,
+ "PCC (processor context corrupt) set\n");
+
+ return 1;
+}
+EXPORT_SYMBOL_GPL(amd64_process_error_info);
+
+
--
1.6.2.4
--
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