[kvm-unit-tests PATCH v4 0/2] UEFI Improvements

[kvm-unit-tests PATCH v4 0/2] UEFI Improvements

[Pavan Kumar Paluri]

Patch-1: Introduces a fix for x86 arch which is ACPI-based to not get
	 into the path of fdt.

Patch-2: KUT UEFI-based guest may sometimes fail to exit boot services
	 due to a possible memory map update that might have taken place
	 between efi_get_memory_map() call and efi_exit_boot_services()
	call. As per UEFI specification (2.10), we need to try and keep
	updating the memory map as long as we get Invalid key failure.

=========
Changelog
=========
v3 -> v4:
    * Dropped patches 3 & 4 from the series as they are not relevant to 
      UEFI improvements introduced in this patchset. This would aid in 
      easier review and upstreaming.
    * Addressed feedback (Andrew)
    * Included R-b tag from Andrew Jones.

v2 -> v3:
    * Included R-b tag from Andrew for Patch-1.
    * Updated patch-2 to not leak memory map information during 
      re-trials to efi_get_memory_map().

v1 -> v2:
    * Incorporated feedback (Andrew, Mike, Tom)
    * Updated patch-2 to keep trying to update memory map and calls to 
      exit boot services as long as there is a failure.
    * Split Page allocation and GHCB page attributes patch into two 
      patches.
 
Pavan Kumar Paluri (2):
  x86 EFI: Bypass call to fdt_check_header()
  x86/efi: Retry call to efi exit boot services

 lib/efi.c | 39 +++++++++++++++++++++++++--------------
 1 file changed, 25 insertions(+), 14 deletions(-)

-- 
2.34.1

[kvm-unit-tests PATCH v4 1/2] x86 EFI: Bypass call to fdt_check_header()

[Pavan Kumar Paluri]

Issuing a call to fdt_check_header() prevents running any of x86 UEFI
enabled tests. Bypass this call for x86 and also calls to
efi_load_image(), efi_grow_buffer(), efi_get_var() in order to enable
UEFI supported tests for KUT x86 arch.

Fixes: 9632ce446b8f ("arm64: efi: Improve device tree discovery")
Signed-off-by: Pavan Kumar Paluri <papaluri@amd.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
---
 lib/efi.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/lib/efi.c b/lib/efi.c
index 5314eaa81e66..8a74a22834a4 100644
--- a/lib/efi.c
+++ b/lib/efi.c
@@ -204,6 +204,7 @@ static char *efi_convert_cmdline(struct efi_loaded_image_64 *image, int *cmd_lin
 	return (char *)cmdline_addr;
 }
 
+#if defined(__aarch64__) || defined(__riscv)
 /*
  * Open the file and read it into a buffer.
  */
@@ -330,6 +331,12 @@ static void *efi_get_fdt(efi_handle_t handle, struct efi_loaded_image_64 *image)
 
 	return fdt_check_header(fdt) == 0 ? fdt : NULL;
 }
+#else
+static void *efi_get_fdt(efi_handle_t handle, struct efi_loaded_image_64 *image)
+{
+	return NULL;
+}
+#endif
 
 static const struct {
 	struct efi_vendor_dev_path	vendor;
-- 
2.34.1

[kvm-unit-tests PATCH v4 2/2] x86/efi: Retry call to efi exit boot services

[Pavan Kumar Paluri]

In some cases, KUT guest might fail to exit boot services due to a
possible memory map update that might have taken place between
efi_get_memory_map() and efi_exit_boot_services() calls. As per UEFI
spec 2.10 (Section 7.4.6 EFI_BOOT_SERVICES.ExitBootServices()), we need
to keep trying to update the memory map and calls to exit boot
services as long as case status is EFI_INVALID_PARAMETER. Keep freeing
the old memory map before obtaining new memory map via
efi_get_memory_map() in case of exit boot services failure.

Signed-off-by: Pavan Kumar Paluri <papaluri@amd.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
---
 lib/efi.c | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/lib/efi.c b/lib/efi.c
index 8a74a22834a4..44337837705d 100644
--- a/lib/efi.c
+++ b/lib/efi.c
@@ -406,8 +406,8 @@ efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab)
 	efi_system_table = sys_tab;
 
 	/* Memory map struct values */
-	efi_memory_desc_t *map = NULL;
-	unsigned long map_size = 0, desc_size = 0, key = 0, buff_size = 0;
+	efi_memory_desc_t *map;
+	unsigned long map_size, desc_size, key, buff_size;
 	u32 desc_ver;
 
 	/* Helper variables needed to get the cmdline */
@@ -446,13 +446,6 @@ efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab)
 	efi_bootinfo.mem_map.key_ptr = &key;
 	efi_bootinfo.mem_map.buff_size = &buff_size;
 
-	/* Get EFI memory map */
-	status = efi_get_memory_map(&efi_bootinfo.mem_map);
-	if (status != EFI_SUCCESS) {
-		printf("Failed to get memory map\n");
-		goto efi_main_error;
-	}
-
 #ifdef __riscv
 	status = efi_get_boot_hartid();
 	if (status != EFI_SUCCESS) {
@@ -461,11 +454,22 @@ efi_status_t efi_main(efi_handle_t handle, efi_system_table_t *sys_tab)
 	}
 #endif
 
-	/* 
-	 * Exit EFI boot services, let kvm-unit-tests take full control of the
-	 * guest
-	 */
-	status = efi_exit_boot_services(handle, &efi_bootinfo.mem_map);
+	status = EFI_INVALID_PARAMETER;
+	while (status == EFI_INVALID_PARAMETER) {
+		status = efi_get_memory_map(&efi_bootinfo.mem_map);
+		if (status != EFI_SUCCESS) {
+			printf("Failed to get memory map\n");
+			goto efi_main_error;
+		}
+		/*
+		 * Exit EFI boot services, let kvm-unit-tests take full
+		 * control of the guest.
+		 */
+		status = efi_exit_boot_services(handle, &efi_bootinfo.mem_map);
+		if (status == EFI_INVALID_PARAMETER)
+			efi_free_pool(*efi_bootinfo.mem_map.map);
+	}
+
 	if (status != EFI_SUCCESS) {
 		printf("Failed to exit boot services\n");
 		goto efi_main_error;
-- 
2.34.1

Re: [kvm-unit-tests PATCH v4 0/2] UEFI Improvements

[Andrew Jones]

On Fri, Mar 29, 2024 at 08:15:20AM -0500, Pavan Kumar Paluri wrote:
> Patch-1: Introduces a fix for x86 arch which is ACPI-based to not get
> 	 into the path of fdt.
> 
> Patch-2: KUT UEFI-based guest may sometimes fail to exit boot services
> 	 due to a possible memory map update that might have taken place
> 	 between efi_get_memory_map() call and efi_exit_boot_services()
> 	call. As per UEFI specification (2.10), we need to try and keep
> 	updating the memory map as long as we get Invalid key failure.
> 
> =========
> Changelog
> =========
> v3 -> v4:
>     * Dropped patches 3 & 4 from the series as they are not relevant to 
>       UEFI improvements introduced in this patchset. This would aid in 
>       easier review and upstreaming.
>     * Addressed feedback (Andrew)
>     * Included R-b tag from Andrew Jones.
> 
> v2 -> v3:
>     * Included R-b tag from Andrew for Patch-1.
>     * Updated patch-2 to not leak memory map information during 
>       re-trials to efi_get_memory_map().
> 
> v1 -> v2:
>     * Incorporated feedback (Andrew, Mike, Tom)
>     * Updated patch-2 to keep trying to update memory map and calls to 
>       exit boot services as long as there is a failure.
>     * Split Page allocation and GHCB page attributes patch into two 
>       patches.
>  
> Pavan Kumar Paluri (2):
>   x86 EFI: Bypass call to fdt_check_header()
>   x86/efi: Retry call to efi exit boot services
> 
>  lib/efi.c | 39 +++++++++++++++++++++++++--------------
>  1 file changed, 25 insertions(+), 14 deletions(-)
> 
> -- 
> 2.34.1
>

Merged.

Thanks,
drew