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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /drivers/firmware/efi/ovmf-debug-log.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'drivers/firmware/efi/ovmf-debug-log.c')
-rw-r--r--drivers/firmware/efi/ovmf-debug-log.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/firmware/efi/ovmf-debug-log.c b/drivers/firmware/efi/ovmf-debug-log.c
new file mode 100644
index 000000000..5b2471ffa
--- /dev/null
+++ b/drivers/firmware/efi/ovmf-debug-log.c
@@ -0,0 +1,111 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/efi.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+
+#define OVMF_DEBUG_LOG_MAGIC1 0x3167646d666d766f // "ovmfmdg1"
+#define OVMF_DEBUG_LOG_MAGIC2 0x3267646d666d766f // "ovmfmdg2"
+
+struct ovmf_debug_log_header {
+ u64 magic1;
+ u64 magic2;
+ u64 hdr_size;
+ u64 log_size;
+ u64 lock; // edk2 spinlock
+ u64 head_off;
+ u64 tail_off;
+ u64 truncated;
+ u8 fw_version[128];
+};
+
+static struct ovmf_debug_log_header *hdr;
+static u8 *logbuf;
+static u64 logbufsize;
+
+static ssize_t ovmf_log_read(struct file *filp, struct kobject *kobj,
+ const struct bin_attribute *attr, char *buf,
+ loff_t offset, size_t count)
+{
+ u64 start, end;
+
+ start = hdr->head_off + offset;
+ if (hdr->head_off > hdr->tail_off && start >= hdr->log_size)
+ start -= hdr->log_size;
+
+ end = start + count;
+ if (start > hdr->tail_off) {
+ if (end > hdr->log_size)
+ end = hdr->log_size;
+ } else {
+ if (end > hdr->tail_off)
+ end = hdr->tail_off;
+ }
+
+ if (start > logbufsize || end > logbufsize)
+ return 0;
+ if (start >= end)
+ return 0;
+
+ memcpy(buf, logbuf + start, end - start);
+ return end - start;
+}
+
+static struct bin_attribute ovmf_log_bin_attr = {
+ .attr = {
+ .name = "ovmf_debug_log",
+ .mode = 0444,
+ },
+ .read = ovmf_log_read,
+};
+
+int __init ovmf_log_probe(unsigned long ovmf_debug_log_table)
+{
+ int ret = -EINVAL;
+ u64 size;
+
+ /* map + verify header */
+ hdr = memremap(ovmf_debug_log_table, sizeof(*hdr), MEMREMAP_WB);
+ if (!hdr) {
+ pr_err("OVMF debug log: header map failed\n");
+ return -EINVAL;
+ }
+
+ if (hdr->magic1 != OVMF_DEBUG_LOG_MAGIC1 ||
+ hdr->magic2 != OVMF_DEBUG_LOG_MAGIC2) {
+ printk(KERN_ERR "OVMF debug log: magic mismatch\n");
+ goto err_unmap;
+ }
+
+ size = hdr->hdr_size + hdr->log_size;
+ pr_info("OVMF debug log: firmware version: \"%s\"\n", hdr->fw_version);
+ pr_info("OVMF debug log: buffer size: %lluk\n", size / 1024);
+
+ /* map complete log buffer */
+ memunmap(hdr);
+ hdr = memremap(ovmf_debug_log_table, size, MEMREMAP_WB);
+ if (!hdr) {
+ pr_err("OVMF debug log: buffer map failed\n");
+ return -EINVAL;
+ }
+ logbuf = (void *)hdr + hdr->hdr_size;
+ logbufsize = hdr->log_size;
+
+ ovmf_log_bin_attr.size = size;
+ ret = sysfs_create_bin_file(efi_kobj, &ovmf_log_bin_attr);
+ if (ret != 0) {
+ pr_err("OVMF debug log: sysfs register failed\n");
+ goto err_unmap;
+ }
+
+ return 0;
+
+err_unmap:
+ memunmap(hdr);
+ return ret;
+}