Spammy devices can flood kernel logs with AER errors and slow/stall execution. Add per-device ratelimits for AER correctable and uncorrectable errors that use the kernel defaults (10 per 5s). Tested using aer-inject[1]. Sent 11 AER errors. Observed 10 errors logged while AER stats (cat /sys/bus/pci/devices/<dev>/aer_dev_correctable) show true count of 11. [1] https://git.kernel.org/pub/scm/linux/kernel/git/gong.chen/aer-inject.git Signed-off-by: Jon Pan-Doh <pandoh@xxxxxxxxxx> Reported-by: Sargun Dhillon <sargun@xxxxxxxx> Acked-by: Paul E. McKenney <paulmck@xxxxxxxxxx> --- drivers/pci/pci.h | 4 +- drivers/pci/pcie/aer.c | 87 ++++++++++++++++++++++++++++++++---------- drivers/pci/pcie/dpc.c | 2 +- 3 files changed, 71 insertions(+), 22 deletions(-) diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h index 9d63d32f041c..f709290e9e00 100644 --- a/drivers/pci/pci.h +++ b/drivers/pci/pci.h @@ -533,6 +533,7 @@ static inline bool pci_dev_test_and_set_removed(struct pci_dev *dev) struct aer_err_info { struct pci_dev *dev[AER_MAX_MULTI_ERR_DEVICES]; + bool ratelimited[AER_MAX_MULTI_ERR_DEVICES]; int error_dev_num; unsigned int id:16; @@ -552,7 +553,8 @@ struct aer_err_info { int aer_get_device_error_info(struct pci_dev *dev, struct aer_err_info *info); void pci_dev_aer_stats_incr(struct pci_dev *pdev, struct aer_err_info *info); -void aer_print_error(struct pci_dev *dev, struct aer_err_info *info, const char *level); +void aer_print_error(struct pci_dev *dev, struct aer_err_info *info, + const char *level, bool ratelimited); int pcie_read_tlp_log(struct pci_dev *dev, int where, int where2, unsigned int tlp_len, bool flit, diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c index f657edca8769..e0f526960134 100644 --- a/drivers/pci/pcie/aer.c +++ b/drivers/pci/pcie/aer.c @@ -28,6 +28,7 @@ #include <linux/interrupt.h> #include <linux/delay.h> #include <linux/kfifo.h> +#include <linux/ratelimit.h> #include <linux/slab.h> #include <acpi/apei.h> #include <acpi/ghes.h> @@ -88,6 +89,10 @@ struct aer_report { u64 rootport_total_cor_errs; u64 rootport_total_fatal_errs; u64 rootport_total_nonfatal_errs; + + /* Ratelimits for errors */ + struct ratelimit_state cor_log_ratelimit; + struct ratelimit_state uncor_log_ratelimit; }; #define AER_LOG_TLP_MASKS (PCI_ERR_UNC_POISON_TLP| \ @@ -379,6 +384,11 @@ void pci_aer_init(struct pci_dev *dev) dev->aer_report = kzalloc(sizeof(*dev->aer_report), GFP_KERNEL); + ratelimit_state_init(&dev->aer_report->cor_log_ratelimit, + DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); + ratelimit_state_init(&dev->aer_report->uncor_log_ratelimit, + DEFAULT_RATELIMIT_INTERVAL, DEFAULT_RATELIMIT_BURST); + /* * We save/restore PCI_ERR_UNCOR_MASK, PCI_ERR_UNCOR_SEVER, * PCI_ERR_COR_MASK, and PCI_ERR_CAP. Root and Root Complex Event @@ -668,6 +678,18 @@ static void pci_rootport_aer_stats_incr(struct pci_dev *pdev, } } +static bool aer_ratelimited(struct pci_dev *dev, unsigned int severity) +{ + struct ratelimit_state *ratelimit; + + if (severity == AER_CORRECTABLE) + ratelimit = &dev->aer_report->cor_log_ratelimit; + else + ratelimit = &dev->aer_report->uncor_log_ratelimit; + + return !__ratelimit(ratelimit); +} + static void __aer_print_error(struct pci_dev *dev, struct aer_err_info *info, const char *level) @@ -693,11 +715,17 @@ static void __aer_print_error(struct pci_dev *dev, } void aer_print_error(struct pci_dev *dev, struct aer_err_info *info, - const char *level) + const char *level, bool ratelimited) { int layer, agent; int id = pci_dev_id(dev); + trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask), + info->severity, info->tlp_header_valid, &info->tlp); + + if (ratelimited) + return; + if (!info->status) { pci_err(dev, "PCIe Bus Error: severity=%s, type=Inaccessible, (Unregistered Agent ID)\n", aer_error_severity_string[info->severity]); @@ -722,21 +750,31 @@ void aer_print_error(struct pci_dev *dev, struct aer_err_info *info, out: if (info->id && info->error_dev_num > 1 && info->id == id) pci_err(dev, " Error of this Agent is reported first\n"); - - trace_aer_event(dev_name(&dev->dev), (info->status & ~info->mask), - info->severity, info->tlp_header_valid, &info->tlp); } static void aer_print_rp_info(struct pci_dev *rp, struct aer_err_info *info) { u8 bus = info->id >> 8; u8 devfn = info->id & 0xff; + struct pci_dev *dev; + bool ratelimited = false; + int i; - pci_info(rp, "%s%s error message received from %04x:%02x:%02x.%d\n", - info->multi_error_valid ? "Multiple " : "", - aer_error_severity_string[info->severity], - pci_domain_nr(rp->bus), bus, PCI_SLOT(devfn), - PCI_FUNC(devfn)); + /* extract endpoint device ratelimit */ + for (i = 0; i < info->error_dev_num; i++) { + dev = info->dev[i]; + if (info->id == pci_dev_id(dev)) { + ratelimited = info->ratelimited[i]; + break; + } + } + + if (!ratelimited) + pci_info(rp, "%s%s error message received from %04x:%02x:%02x.%d\n", + info->multi_error_valid ? "Multiple " : "", + aer_error_severity_string[info->severity], + pci_domain_nr(rp->bus), bus, PCI_SLOT(devfn), + PCI_FUNC(devfn)); } #ifdef CONFIG_ACPI_APEI_PCIEAER @@ -784,6 +822,12 @@ void pci_print_aer(struct pci_dev *dev, int aer_severity, pci_dev_aer_stats_incr(dev, &info); + trace_aer_event(dev_name(&dev->dev), (status & ~mask), + aer_severity, tlp_header_valid, &aer->header_log); + + if (aer_ratelimited(dev, aer_severity)) + return; + aer_printk(level, dev, "aer_status: 0x%08x, aer_mask: 0x%08x\n", status, mask); __aer_print_error(dev, &info, level); aer_printk(level, dev, "aer_layer=%s, aer_agent=%s\n", @@ -795,9 +839,6 @@ void pci_print_aer(struct pci_dev *dev, int aer_severity, if (tlp_header_valid) pcie_print_tlp_log(dev, &aer->header_log, dev_fmt(" ")); - - trace_aer_event(dev_name(&dev->dev), (status & ~mask), - aer_severity, tlp_header_valid, &aer->header_log); } EXPORT_SYMBOL_NS_GPL(pci_print_aer, "CXL"); @@ -808,8 +849,12 @@ EXPORT_SYMBOL_NS_GPL(pci_print_aer, "CXL"); */ static int add_error_device(struct aer_err_info *e_info, struct pci_dev *dev) { - if (e_info->error_dev_num < AER_MAX_MULTI_ERR_DEVICES) { - e_info->dev[e_info->error_dev_num] = pci_dev_get(dev); + int dev_idx = e_info->error_dev_num; + unsigned int severity = e_info->severity; + + if (dev_idx < AER_MAX_MULTI_ERR_DEVICES) { + e_info->dev[dev_idx] = pci_dev_get(dev); + e_info->ratelimited[dev_idx] = aer_ratelimited(dev, severity); e_info->error_dev_num++; return 0; } @@ -1265,7 +1310,8 @@ static inline void aer_process_err_devices(struct aer_err_info *e_info, for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) { if (aer_get_device_error_info(e_info->dev[i], e_info)) { pci_dev_aer_stats_incr(e_info->dev[i], e_info); - aer_print_error(e_info->dev[i], e_info, level); + aer_print_error(e_info->dev[i], e_info, level, + e_info->ratelimited[i]); } } for (i = 0; i < e_info->error_dev_num && e_info->dev[i]; i++) { @@ -1299,10 +1345,11 @@ static void aer_isr_one_error(struct aer_rpc *rpc, e_info.multi_error_valid = 1; else e_info.multi_error_valid = 0; - aer_print_rp_info(pdev, &e_info); - if (find_source_device(pdev, &e_info)) + if (find_source_device(pdev, &e_info)) { + aer_print_rp_info(pdev, &e_info); aer_process_err_devices(&e_info, KERN_WARNING); + } } if (e_src->status & PCI_ERR_ROOT_UNCOR_RCV) { @@ -1318,10 +1365,10 @@ static void aer_isr_one_error(struct aer_rpc *rpc, else e_info.multi_error_valid = 0; - aer_print_rp_info(pdev, &e_info); - - if (find_source_device(pdev, &e_info)) + if (find_source_device(pdev, &e_info)) { + aer_print_rp_info(pdev, &e_info); aer_process_err_devices(&e_info, KERN_ERR); + } } } diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index 81cd6e8ff3a4..42a36df4a651 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -290,7 +290,7 @@ void dpc_process_error(struct pci_dev *pdev) dpc_get_aer_uncorrect_severity(pdev, &info) && aer_get_device_error_info(pdev, &info)) { pci_dev_aer_stats_incr(pdev, &info); - aer_print_error(pdev, &info, KERN_ERR); + aer_print_error(pdev, &info, KERN_ERR, false); pci_aer_clear_nonfatal_status(pdev); pci_aer_clear_fatal_status(pdev); } -- 2.49.0.395.g12beb8f557-goog
