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Diffstat (limited to 'drivers/firmware/efi')
-rw-r--r--drivers/firmware/efi/Kconfig7
-rw-r--r--drivers/firmware/efi/efi-init.c29
-rw-r--r--drivers/firmware/efi/libstub/x86-stub.c14
3 files changed, 38 insertions, 12 deletions
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index d528c94c5859..29e0729299f5 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -267,9 +267,10 @@ 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).
+ Recent versions of the Open Virtual Machine Firmware
+ (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
diff --git a/drivers/firmware/efi/efi-init.c b/drivers/firmware/efi/efi-init.c
index a00e07b853f2..a65c2d5b9e7b 100644
--- a/drivers/firmware/efi/efi-init.c
+++ b/drivers/firmware/efi/efi-init.c
@@ -12,6 +12,7 @@
#include <linux/efi.h>
#include <linux/fwnode.h>
#include <linux/init.h>
+#include <linux/kexec_handover.h>
#include <linux/memblock.h>
#include <linux/mm_types.h>
#include <linux/of.h>
@@ -164,12 +165,32 @@ static __init void reserve_regions(void)
pr_info("Processing EFI memory map:\n");
/*
- * Discard memblocks discovered so far: if there are any at this
- * point, they originate from memory nodes in the DT, and UEFI
- * uses its own memory map instead.
+ * Discard memblocks discovered so far except for KHO scratch
+ * regions. Most memblocks at this point originate from memory nodes
+ * in the DT and UEFI uses its own memory map instead. However, if
+ * KHO is enabled, scratch regions, which are good known memory
+ * must be preserved.
*/
memblock_dump_all();
- memblock_remove(0, PHYS_ADDR_MAX);
+
+ if (is_kho_boot()) {
+ struct memblock_region *r;
+
+ /* Remove all non-KHO regions */
+ for_each_mem_region(r) {
+ if (!memblock_is_kho_scratch(r)) {
+ memblock_remove(r->base, r->size);
+ r--;
+ }
+ }
+ } else {
+ /*
+ * KHO is disabled. Discard memblocks discovered so far:
+ * if there are any at this point, they originate from memory
+ * nodes in the DT, and UEFI uses its own memory map instead.
+ */
+ memblock_remove(0, PHYS_ADDR_MAX);
+ }
for_each_efi_memory_desc(md) {
paddr = md->phys_addr;
diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c
index cafc90d4caaf..761121a77f9e 100644
--- a/drivers/firmware/efi/libstub/x86-stub.c
+++ b/drivers/firmware/efi/libstub/x86-stub.c
@@ -300,7 +300,7 @@ efi_status_t efi_adjust_memory_range_protection(unsigned long start,
return EFI_SUCCESS;
/*
- * Don't modify memory region attributes, they are
+ * Don't modify memory region attributes, if they are
* already suitable, to lower the possibility to
* encounter firmware bugs.
*/
@@ -315,11 +315,13 @@ efi_status_t efi_adjust_memory_range_protection(unsigned long start,
next = desc.base_address + desc.length;
/*
- * Only system memory is suitable for trampoline/kernel image placement,
- * so only this type of memory needs its attributes to be modified.
+ * Only system memory and more reliable memory are suitable for
+ * trampoline/kernel image placement. So only those memory types
+ * may need to have attributes modified.
*/
- if (desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory ||
+ if ((desc.gcd_memory_type != EfiGcdMemoryTypeSystemMemory &&
+ desc.gcd_memory_type != EfiGcdMemoryTypeMoreReliable) ||
(desc.attributes & (EFI_MEMORY_RO | EFI_MEMORY_XP)) == 0)
continue;
@@ -788,7 +790,9 @@ static efi_status_t efi_decompress_kernel(unsigned long *kernel_entry,
*kernel_entry = addr + entry;
- return efi_adjust_memory_range_protection(addr, kernel_text_size);
+ return efi_adjust_memory_range_protection(addr, kernel_text_size) ?:
+ efi_adjust_memory_range_protection(addr + kernel_inittext_offset,
+ kernel_inittext_size);
}
static void __noreturn enter_kernel(unsigned long kernel_addr,