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Diffstat (limited to 'drivers/firmware/efi')
-rw-r--r--drivers/firmware/efi/Kconfig10
-rw-r--r--drivers/firmware/efi/Makefile1
-rw-r--r--drivers/firmware/efi/efi.c8
-rw-r--r--drivers/firmware/efi/libstub/Makefile8
-rw-r--r--drivers/firmware/efi/libstub/Makefile.zboot2
-rw-r--r--drivers/firmware/efi/libstub/printk.c4
-rw-r--r--drivers/firmware/efi/libstub/zboot.lds6
-rw-r--r--drivers/firmware/efi/mokvar-table.c2
-rw-r--r--drivers/firmware/efi/ovmf-debug-log.c111
9 files changed, 139 insertions, 13 deletions
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index db8c5c03d3a2..d528c94c5859 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -263,6 +263,14 @@ config EFI_COCO_SECRET
virt/coco/efi_secret module to access the secrets, which in turn
allows userspace programs to access the injected secrets.
+config OVMF_DEBUG_LOG
+ bool "Expose OVMF firmware debug log via sysfs"
+ depends on EFI
+ help
+ Recent OVMF versions (edk2-stable202508 + newer) can write
+ their debug log to a memory buffer. This driver exposes the
+ log content via sysfs (/sys/firmware/efi/ovmf_debug_log).
+
config UNACCEPTED_MEMORY
bool
depends on EFI_STUB
@@ -286,7 +294,7 @@ config EFI_SBAT
config EFI_SBAT_FILE
string "Embedded SBAT section file path"
- depends on EFI_ZBOOT
+ depends on EFI_ZBOOT || (EFI_STUB && X86)
help
SBAT section provides a way to improve SecureBoot revocations of UEFI
binaries by introducing a generation-based mechanism. With SBAT, older
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index a2d0009560d0..8efbcf699e4f 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_APPLE_PROPERTIES) += apple-properties.o
obj-$(CONFIG_EFI_RCI2_TABLE) += rci2-table.o
obj-$(CONFIG_EFI_EMBEDDED_FIRMWARE) += embedded-firmware.o
obj-$(CONFIG_LOAD_UEFI_KEYS) += mokvar-table.o
+obj-$(CONFIG_OVMF_DEBUG_LOG) += ovmf-debug-log.o
obj-$(CONFIG_SYSFB) += sysfb_efi.o
diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c
index e57bff702b5f..1ce428e2ac8a 100644
--- a/drivers/firmware/efi/efi.c
+++ b/drivers/firmware/efi/efi.c
@@ -45,6 +45,7 @@ struct efi __read_mostly efi = {
.esrt = EFI_INVALID_TABLE_ADDR,
.tpm_log = EFI_INVALID_TABLE_ADDR,
.tpm_final_log = EFI_INVALID_TABLE_ADDR,
+ .ovmf_debug_log = EFI_INVALID_TABLE_ADDR,
#ifdef CONFIG_LOAD_UEFI_KEYS
.mokvar_table = EFI_INVALID_TABLE_ADDR,
#endif
@@ -473,6 +474,10 @@ static int __init efisubsys_init(void)
platform_device_register_simple("efi_secret", 0, NULL, 0);
#endif
+ if (IS_ENABLED(CONFIG_OVMF_DEBUG_LOG) &&
+ efi.ovmf_debug_log != EFI_INVALID_TABLE_ADDR)
+ ovmf_log_probe(efi.ovmf_debug_log);
+
return 0;
err_remove_group:
@@ -617,6 +622,9 @@ static const efi_config_table_type_t common_tables[] __initconst = {
{LINUX_EFI_MEMRESERVE_TABLE_GUID, &mem_reserve, "MEMRESERVE" },
{LINUX_EFI_INITRD_MEDIA_GUID, &initrd, "INITRD" },
{EFI_RT_PROPERTIES_TABLE_GUID, &rt_prop, "RTPROP" },
+#ifdef CONFIG_OVMF_DEBUG_LOG
+ {OVMF_MEMORY_LOG_TABLE_GUID, &efi.ovmf_debug_log, "OvmfDebugLog" },
+#endif
#ifdef CONFIG_EFI_RCI2_TABLE
{DELLEMC_EFI_RCI2_TABLE_GUID, &rci2_table_phys },
#endif
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index 939a4955e00b..94b05e4451dd 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -22,16 +22,16 @@ cflags-$(CONFIG_X86) += -m$(BITS) -D__KERNEL__ -std=gnu11 \
# arm64 uses the full KBUILD_CFLAGS so it's necessary to explicitly
# disable the stackleak plugin
-cflags-$(CONFIG_ARM64) += -fpie $(DISABLE_STACKLEAK_PLUGIN) \
+cflags-$(CONFIG_ARM64) += -fpie $(DISABLE_KSTACK_ERASE) \
-fno-unwind-tables -fno-asynchronous-unwind-tables
cflags-$(CONFIG_ARM) += -DEFI_HAVE_STRLEN -DEFI_HAVE_STRNLEN \
-DEFI_HAVE_MEMCHR -DEFI_HAVE_STRRCHR \
-DEFI_HAVE_STRCMP -fno-builtin -fpic \
$(call cc-option,-mno-single-pic-base) \
- $(DISABLE_STACKLEAK_PLUGIN)
+ $(DISABLE_KSTACK_ERASE)
cflags-$(CONFIG_RISCV) += -fpic -DNO_ALTERNATIVE -mno-relax \
- $(DISABLE_STACKLEAK_PLUGIN)
-cflags-$(CONFIG_LOONGARCH) += -fpie $(DISABLE_STACKLEAK_PLUGIN)
+ $(DISABLE_KSTACK_ERASE)
+cflags-$(CONFIG_LOONGARCH) += -fpie $(DISABLE_KSTACK_ERASE)
cflags-$(CONFIG_EFI_PARAMS_FROM_FDT) += -I$(srctree)/scripts/dtc/libfdt
diff --git a/drivers/firmware/efi/libstub/Makefile.zboot b/drivers/firmware/efi/libstub/Makefile.zboot
index 92e3c73502ba..832deee36e48 100644
--- a/drivers/firmware/efi/libstub/Makefile.zboot
+++ b/drivers/firmware/efi/libstub/Makefile.zboot
@@ -36,7 +36,7 @@ aflags-zboot-header-$(EFI_ZBOOT_FORWARD_CFI) := \
-DPE_DLL_CHAR_EX=IMAGE_DLLCHARACTERISTICS_EX_FORWARD_CFI_COMPAT
AFLAGS_zboot-header.o += -DMACHINE_TYPE=IMAGE_FILE_MACHINE_$(EFI_ZBOOT_MACH_TYPE) \
- -DZBOOT_EFI_PATH="\"$(realpath $(obj)/vmlinuz.efi.elf)\"" \
+ -DZBOOT_EFI_PATH="\"$(abspath $(obj)/vmlinuz.efi.elf)\"" \
-DZBOOT_SIZE_LEN=$(zboot-size-len-y) \
-DCOMP_TYPE="\"$(comp-type-y)\"" \
$(aflags-zboot-header-y)
diff --git a/drivers/firmware/efi/libstub/printk.c b/drivers/firmware/efi/libstub/printk.c
index 3a67a2cea7bd..bc599212c05d 100644
--- a/drivers/firmware/efi/libstub/printk.c
+++ b/drivers/firmware/efi/libstub/printk.c
@@ -5,13 +5,13 @@
#include <linux/ctype.h>
#include <linux/efi.h>
#include <linux/kernel.h>
-#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */
+#include <linux/kern_levels.h>
#include <asm/efi.h>
#include <asm/setup.h>
#include "efistub.h"
-int efi_loglevel = CONSOLE_LOGLEVEL_DEFAULT;
+int efi_loglevel = LOGLEVEL_NOTICE;
/**
* efi_char16_puts() - Write a UCS-2 encoded string to the console
diff --git a/drivers/firmware/efi/libstub/zboot.lds b/drivers/firmware/efi/libstub/zboot.lds
index c3a166675450..367907eb7d86 100644
--- a/drivers/firmware/efi/libstub/zboot.lds
+++ b/drivers/firmware/efi/libstub/zboot.lds
@@ -29,14 +29,12 @@ SECTIONS
. = _etext;
}
-#ifdef CONFIG_EFI_SBAT
.sbat : ALIGN(4096) {
_sbat = .;
*(.sbat)
_esbat = ALIGN(4096);
. = _esbat;
}
-#endif
.data : ALIGN(4096) {
_data = .;
@@ -60,6 +58,6 @@ SECTIONS
PROVIDE(__efistub__gzdata_size =
ABSOLUTE(__efistub__gzdata_end - __efistub__gzdata_start));
-PROVIDE(__data_rawsize = ABSOLUTE(_edata - _etext));
-PROVIDE(__data_size = ABSOLUTE(_end - _etext));
+PROVIDE(__data_rawsize = ABSOLUTE(_edata - _data));
+PROVIDE(__data_size = ABSOLUTE(_end - _data));
PROVIDE(__sbat_size = ABSOLUTE(_esbat - _sbat));
diff --git a/drivers/firmware/efi/mokvar-table.c b/drivers/firmware/efi/mokvar-table.c
index 0a856c3f69a3..aedbbd627706 100644
--- a/drivers/firmware/efi/mokvar-table.c
+++ b/drivers/firmware/efi/mokvar-table.c
@@ -340,7 +340,7 @@ static int __init efi_mokvar_sysfs_init(void)
mokvar_sysfs->bin_attr.attr.name = mokvar_entry->name;
mokvar_sysfs->bin_attr.attr.mode = 0400;
mokvar_sysfs->bin_attr.size = mokvar_entry->data_size;
- mokvar_sysfs->bin_attr.read_new = efi_mokvar_sysfs_read;
+ mokvar_sysfs->bin_attr.read = efi_mokvar_sysfs_read;
err = sysfs_create_bin_file(mokvar_kobj,
&mokvar_sysfs->bin_attr);
diff --git a/drivers/firmware/efi/ovmf-debug-log.c b/drivers/firmware/efi/ovmf-debug-log.c
new file mode 100644
index 000000000000..5b2471ffaeed
--- /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;
+}
generated by cgit (git 2.34.1) at 2025-08-09 21:29:15 +0000