x86, efi: EFI boot stub config file support

RFC PATCH In review Shea Levy 3 participants 6 messages Mar 18, 2012 – Jun 2, 2012 x86

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Shea Levy

author

2012-03-18 15:45 UTC #0 lore raw

RFC PATCH 1/1 x86, efi: EFI boot stub config file support

Hello,

Inlined is a patch to have the kernel read its parameters from a config file when booted via the EFI boot stub without any parameters passed. This patch roughly follows the plan I discussed when proposing this idea, except now the file is found relative to the location of the bzImage and there is no additional check to see if image->parent_handle is NULL (despite the spec saying it will be NULL when the image was loaded by the firmware itself, it was never NULL on any of the systems I tested).

Cheers,
Shea Levy

---

From 2c12b0f49831d2d96b6bdcef931794178312c288 Mon Sep 17 00:00:00 2001
From: Shea Levy <[email protected]>
Date: Sun, 18 Mar 2012 16:17:04 +0100
Subject: [PATCH 1/1] x86, efi: EFI boot stub config file support

When booting via the EFI boot stub, search for a file named 'linux.conf' in the same directory as the bzImage and read the kernel command line from it when no load options are passed.

The file search should only be triggered when the bzImage is loaded from the firmware's boot process. When loaded via an EFI shell, the load options always contain at least one character, even if no parameters were passed at the prompt.

Signed-off-by Shea Levy <[email protected]>

---
 arch/x86/boot/compressed/eboot.c |  146 
++++++++++++++++++++++++++++++++++++--
 arch/x86/boot/compressed/eboot.h |    2 +
 2 files changed, 143 insertions(+), 5 deletions(-)

arch/x86/boot/compressed/eboot.c +141 -5

index fec216f..672ecfe 100644
@@ -486,14 +486,14 @@ struct initrd {
  * kernel image.
  */
 static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
-                    struct setup_header *hdr)
+                    struct setup_header *hdr,
+                    efi_file_handle_t *fh)
 {
     struct initrd *initrds;
     unsigned long initrd_addr;
     efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
     u64 initrd_total;
     efi_file_io_interface_t *io;
-    efi_file_handle_t *fh;
     efi_status_t status;
     int nr_initrds;
     char *str;

@@ -568,7 +568,7 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
         *p = '\0';
 
         /* Only open the volume once. */
-        if (!i) {
+        if (!fh) {
             efi_boot_services_t *boottime;
 
             boottime = sys_table->boottime;

@@ -712,6 +712,7 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
     u16 *s2;
     u8 *s1;
     int i;
+    efi_file_handle_t *fh = NULL;
 
     hdr->type_of_loader = 0x21;

@@ -743,14 +744,149 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
 
             *s1 = '\0';
         }
-    }
+    } else {
+        efi_char16_t config_file_name[
+            sizeof CONFIG_FILE_NAME * sizeof(efi_char16_t)];
+        u16 *file_path = (u16 *)image->file_path;
+        efi_char16_t config_path[256], *config_path_position;
+        efi_boot_services_t *boottime;
+        efi_file_info_t *info;
+        unsigned long info_sz = 0;
+        u64 file_sz;
+        efi_guid_t info_guid = EFI_FILE_INFO_ID;
+        efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+        efi_file_io_interface_t *io;
+        efi_file_handle_t *h;
+
+        boottime = sys_table->boottime;
+
+        config_path_position = config_path;
+
+        for (i = 0; i < sizeof CONFIG_FILE_NAME; i++)
+            config_file_name[i] = CONFIG_FILE_NAME[i];
+
+        while (*file_path == 0x404) {
+            u16 node_size = *(file_path + 1)/sizeof *file_path;
+
+            if (config_path_position - config_path) {
+                if (*(file_path + 2) == '\\' &&
+                        *(file_path - 2) == '\\') {
+                    config_path_position--;
+                } else if (*(file_path + 2) != '\\' &&
+                        *(file_path - 2) != '\\') {
+                    *config_path_position++ = '\\';
+                }
+            }
+
+            if ((config_path_position - config_path) + node_size - 3
+                    + sizeof config_file_name
+                    / sizeof *config_file_name
+ > sizeof config_path
+                    / sizeof *config_path)
+                goto end;
+
+            memcpy((void *)config_path_position, file_path + 2,
+                    (node_size - 3) * sizeof *config_path);
 
+            config_path_position += node_size - 3;
+            file_path += node_size;
+        }
+
+        while (*config_path_position != '\\' && config_path_position !=
+                config_path)
+            config_path_position--;
+
+        *config_path_position = '\\';
+
+        memcpy((void *)(config_path_position + 1),
+                config_file_name,
+                sizeof config_file_name);
+
+        status = efi_call_phys3(boottime->handle_protocol,
+                image->device_handle, &fs_proto, &io);
+
+        if (status != EFI_SUCCESS)
+            goto end;
+
+        status = efi_call_phys2(io->open_volume, io, &fh);
+
+        if (status != EFI_SUCCESS) {
+            fh = NULL;
+            goto end;
+        }
+
+        status = efi_call_phys5(fh->open,
+                fh,
+ &h,
+                config_path,
+                EFI_FILE_MODE_READ, (u64)0);
+
+        if (status != EFI_SUCCESS)
+            goto end;
+
+        status = efi_call_phys4(h->get_info, h, &info_guid,
+ &info_sz, NULL);
+
+        if (status != EFI_BUFFER_TOO_SMALL)
+            goto close_config_file;
+
+        while (status == EFI_BUFFER_TOO_SMALL) {
+            status = efi_call_phys3(boottime->allocate_pool,
+                    EFI_LOADER_DATA, info_sz, &info);
+
+            if (status != EFI_SUCCESS)
+                goto close_config_file;
+
+            status = efi_call_phys4(h->get_info, h, &info_guid,
+ &info_sz, info);
+
+            if (status == EFI_BUFFER_TOO_SMALL)
+                efi_call_phys1(boottime->free_pool, info);
+        }
+
+        if (status != EFI_SUCCESS)
+            goto free_config_file_info;
+
+        file_sz = info->file_size;
+
+        if (file_sz > hdr->cmdline_size)
+            file_sz = hdr->cmdline_size;
+
+        options_size = file_sz + 1;
+
+        status = low_alloc(options_size, 1, &cmdline);
+
+        if (status != EFI_SUCCESS)
+            goto free_config_file_info;
+
+        status = efi_call_phys3(h->read, h, &file_sz, cmdline);
+
+        if (status != EFI_SUCCESS)
+            goto free_config_file_cmdline;
+
+        *((u8 *)cmdline + file_sz) = 0;
+
+        goto free_config_file_info;
+free_config_file_cmdline:
+        low_free(options_size, cmdline);
+        cmdline = 0;
+        options_size = 0;
+free_config_file_info:
+        efi_call_phys1(boottime->free_pool, info);
+close_config_file:
+        efi_call_phys1(h->close, h);
+    }
+end:
     hdr->cmd_line_ptr = cmdline;
 
     hdr->ramdisk_image = 0;
     hdr->ramdisk_size = 0;
 
-    status = handle_ramdisks(image, hdr);
+    status = handle_ramdisks(image, hdr, fh);
+
+    if (fh)
+        efi_call_phys1(fh->close, fh);
+
     if (status != EFI_SUCCESS)
         goto free_cmdline;

arch/x86/boot/compressed/eboot.h +2 -0

index 3925166..186b4c6 100644
@@ -20,6 +20,8 @@
 #define PIXEL_BLT_ONLY                    3
 #define PIXEL_FORMAT_MAX                4
 
+#define CONFIG_FILE_NAME "linux.conf"
+
 struct efi_pixel_bitmask {
     u32 red_mask;
     u32 green_mask;

Signature · 1 line

1.7.9.4

Shea Levy

author

2012-03-18 15:49 UTC #1 lore raw

Quoted 228 lines · Shea Levy

Hello,

Cheers,
Shea Levy

---

When booting via the EFI boot stub, search for a file named 'linux.conf' in the same directory as the bzImage and read the kernel command line from it when no load options are passed.

Signed-off-by Shea Levy <[email protected]>

---
 arch/x86/boot/compressed/eboot.c |  146 
++++++++++++++++++++++++++++++++++++--
 arch/x86/boot/compressed/eboot.h |    2 +
 2 files changed, 143 insertions(+), 5 deletions(-)

arch/x86/boot/compressed/eboot.c +3 -3

index fec216f..672ecfe 100644
@@ -486,14 +486,14 @@ struct initrd {
  * kernel image.
  */
 static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
-                    struct setup_header *hdr)
+                    struct setup_header *hdr,
+                    efi_file_handle_t *fh)
 {
     struct initrd *initrds;
     unsigned long initrd_addr;
     efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
     u64 initrd_total;
     efi_file_io_interface_t *io;
-    efi_file_handle_t *fh;
     efi_status_t status;
     int nr_initrds;
     char *str;

@@ -568,7 +568,7 @@ static efi_status_t 
 handle_ramdisks(efi_loaded_image_t *image,
         *p = '\0';
 
         /* Only open the volume once. */
-        if (!i) {
+        if (!fh) {
             efi_boot_services_t *boottime;

             boottime = sys_table->boottime;

arch/x86/boot/compressed/eboot.c +138 -2

@@ -712,6 +712,7 @@ static efi_status_t make_boot_params(struct 
 boot_params *boot_params,
     u16 *s2;
     u8 *s1;
     int i;
+    efi_file_handle_t *fh = NULL;
 
     hdr->type_of_loader = 0x21;

@@ -743,14 +744,149 @@ static efi_status_t make_boot_params(struct 
 boot_params *boot_params,
 
             *s1 = '\0';
         }
-    }
+    } else {
+        efi_char16_t config_file_name[
+            sizeof CONFIG_FILE_NAME * sizeof(efi_char16_t)];
+        u16 *file_path = (u16 *)image->file_path;
+        efi_char16_t config_path[256], *config_path_position;
+        efi_boot_services_t *boottime;
+        efi_file_info_t *info;
+        unsigned long info_sz = 0;
+        u64 file_sz;
+        efi_guid_t info_guid = EFI_FILE_INFO_ID;
+        efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+        efi_file_io_interface_t *io;
+        efi_file_handle_t *h;
+
+        boottime = sys_table->boottime;
+
+        config_path_position = config_path;
+
+        for (i = 0; i < sizeof CONFIG_FILE_NAME; i++)
+            config_file_name[i] = CONFIG_FILE_NAME[i];
+
+        while (*file_path == 0x404) {
+            u16 node_size = *(file_path + 1)/sizeof *file_path;
+
+            if (config_path_position - config_path) {
+                if (*(file_path + 2) == '\\' &&
+                        *(file_path - 2) == '\\') {
+                    config_path_position--;
+                } else if (*(file_path + 2) != '\\' &&
+                        *(file_path - 2) != '\\') {
+                    *config_path_position++ = '\\';
+                }
+            }
+
+            if ((config_path_position - config_path) + node_size - 3
+                    + sizeof config_file_name
+                    / sizeof *config_file_name
+ > sizeof config_path
+                    / sizeof *config_path)
+                goto end;
+
+            memcpy((void *)config_path_position, file_path + 2,
+                    (node_size - 3) * sizeof *config_path);
 
+            config_path_position += node_size - 3;
+            file_path += node_size;
+        }
+
+        while (*config_path_position != '\\' && config_path_position !=
+                config_path)
+            config_path_position--;
+
+        *config_path_position = '\\';
+
+        memcpy((void *)(config_path_position + 1),
+                config_file_name,
+                sizeof config_file_name);
+
+        status = efi_call_phys3(boottime->handle_protocol,
+                image->device_handle, &fs_proto, &io);
+
+        if (status != EFI_SUCCESS)
+            goto end;
+
+        status = efi_call_phys2(io->open_volume, io, &fh);
+
+        if (status != EFI_SUCCESS) {
+            fh = NULL;
+            goto end;
+        }
+
+        status = efi_call_phys5(fh->open,
+                fh,
+ &h,
+                config_path,
+                EFI_FILE_MODE_READ, (u64)0);
+
+        if (status != EFI_SUCCESS)
+            goto end;
+
+        status = efi_call_phys4(h->get_info, h, &info_guid,
+ &info_sz, NULL);
+
+        if (status != EFI_BUFFER_TOO_SMALL)
+            goto close_config_file;
+
+        while (status == EFI_BUFFER_TOO_SMALL) {
+            status = efi_call_phys3(boottime->allocate_pool,
+                    EFI_LOADER_DATA, info_sz, &info);
+
+            if (status != EFI_SUCCESS)
+                goto close_config_file;
+
+            status = efi_call_phys4(h->get_info, h, &info_guid,
+ &info_sz, info);
+
+            if (status == EFI_BUFFER_TOO_SMALL)
+                efi_call_phys1(boottime->free_pool, info);
+        }
+
+        if (status != EFI_SUCCESS)
+            goto free_config_file_info;
+
+        file_sz = info->file_size;
+
+        if (file_sz > hdr->cmdline_size)
+            file_sz = hdr->cmdline_size;
+
+        options_size = file_sz + 1;
+
+        status = low_alloc(options_size, 1, &cmdline);
+
+        if (status != EFI_SUCCESS)
+            goto free_config_file_info;
+
+        status = efi_call_phys3(h->read, h, &file_sz, cmdline);
+
+        if (status != EFI_SUCCESS)
+            goto free_config_file_cmdline;
+
+        *((u8 *)cmdline + file_sz) = 0;
+
+        goto free_config_file_info;
+free_config_file_cmdline:
+        low_free(options_size, cmdline);
+        cmdline = 0;
+        options_size = 0;
+free_config_file_info:
+        efi_call_phys1(boottime->free_pool, info);
+close_config_file:
+        efi_call_phys1(h->close, h);
+    }
+end:
     hdr->cmd_line_ptr = cmdline;
 
     hdr->ramdisk_image = 0;
     hdr->ramdisk_size = 0;
 
-    status = handle_ramdisks(image, hdr);
+    status = handle_ramdisks(image, hdr, fh);
+
+    if (fh)
+        efi_call_phys1(fh->close, fh);
+
     if (status != EFI_SUCCESS)
         goto free_cmdline;

arch/x86/boot/compressed/eboot.h +0 -0

index 3925166..186b4c6 100644

arch/x86/boot/compressed/eboot.h line 27

Quoted 8 lines

arch/x86/boot/compressed/eboot.h +2 -0

@@ -20,6 +20,8 @@
 #define PIXEL_BLT_ONLY                    3
 #define PIXEL_FORMAT_MAX                4
 
+#define CONFIG_FILE_NAME "linux.conf"
+
 struct efi_pixel_bitmask {
     u32 red_mask;
     u32 green_mask;

Hmm, my mail client seems to have mangled the patch. I've attached it here.

Quoted 1 line

From 2c12b0f49831d2d96b6bdcef931794178312c288 Mon Sep 17 00:00:00 2001

From: Shea Levy <[email protected]>
Date: Sun, 18 Mar 2012 16:17:04 +0100
Subject: [PATCH 1/1] x86, efi: EFI boot stub config file support

When booting via the EFI boot stub, search for a file named 'linux.conf' in the same directory as the bzImage and read the kernel command line from it when no load options are passed.

Signed-off-by Shea Levy <[email protected]>

---
 arch/x86/boot/compressed/eboot.c |  146 ++++++++++++++++++++++++++++++++++++--
 arch/x86/boot/compressed/eboot.h |    2 +
 2 files changed, 143 insertions(+), 5 deletions(-)

arch/x86/boot/compressed/eboot.c +141 -5

index fec216f..672ecfe 100644
@@ -486,14 +486,14 @@ struct initrd {
  * kernel image.
  */
 static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
-				    struct setup_header *hdr)
+				    struct setup_header *hdr,
+				    efi_file_handle_t *fh)
 {
 	struct initrd *initrds;
 	unsigned long initrd_addr;
 	efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
 	u64 initrd_total;
 	efi_file_io_interface_t *io;
-	efi_file_handle_t *fh;
 	efi_status_t status;
 	int nr_initrds;
 	char *str;

@@ -568,7 +568,7 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image,
 		*p = '\0';
 
 		/* Only open the volume once. */
-		if (!i) {
+		if (!fh) {
 			efi_boot_services_t *boottime;
 
 			boottime = sys_table->boottime;

@@ -712,6 +712,7 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
 	u16 *s2;
 	u8 *s1;
 	int i;
+	efi_file_handle_t *fh = NULL;
 
 	hdr->type_of_loader = 0x21;

@@ -743,14 +744,149 @@ static efi_status_t make_boot_params(struct boot_params *boot_params,
 
 			*s1 = '\0';
 		}
-	}
+	} else {
+		efi_char16_t config_file_name[
+			sizeof CONFIG_FILE_NAME * sizeof(efi_char16_t)];
+		u16 *file_path = (u16 *)image->file_path;
+		efi_char16_t config_path[256], *config_path_position;
+		efi_boot_services_t *boottime;
+		efi_file_info_t *info;
+		unsigned long info_sz = 0;
+		u64 file_sz;
+		efi_guid_t info_guid = EFI_FILE_INFO_ID;
+		efi_guid_t fs_proto = EFI_FILE_SYSTEM_GUID;
+		efi_file_io_interface_t *io;
+		efi_file_handle_t *h;
+
+		boottime = sys_table->boottime;
+
+		config_path_position = config_path;
+
+		for (i = 0; i < sizeof CONFIG_FILE_NAME; i++)
+			config_file_name[i] = CONFIG_FILE_NAME[i];
+
+		while (*file_path == 0x404) {
+			u16 node_size = *(file_path + 1)/sizeof *file_path;
+
+			if (config_path_position - config_path) {
+				if (*(file_path + 2) == '\\' &&
+						*(file_path - 2) == '\\') {
+					config_path_position--;
+				} else if (*(file_path + 2) != '\\' &&
+						*(file_path - 2) != '\\') {
+					*config_path_position++ = '\\';
+				}
+			}
+
+			if ((config_path_position - config_path) + node_size - 3
+					+ sizeof config_file_name
+					/ sizeof *config_file_name
+					> sizeof config_path
+					/ sizeof *config_path)
+				goto end;
+
+			memcpy((void *)config_path_position, file_path + 2,
+					(node_size - 3) * sizeof *config_path);
 
+			config_path_position += node_size - 3;
+			file_path += node_size;
+		}
+
+		while (*config_path_position != '\\' && config_path_position !=
+				config_path)
+			config_path_position--;
+
+		*config_path_position = '\\';
+
+		memcpy((void *)(config_path_position + 1),
+				config_file_name,
+				sizeof config_file_name);
+
+		status = efi_call_phys3(boottime->handle_protocol,
+				image->device_handle, &fs_proto, &io);
+
+		if (status != EFI_SUCCESS)
+			goto end;
+
+		status = efi_call_phys2(io->open_volume, io, &fh);
+
+		if (status != EFI_SUCCESS) {
+			fh = NULL;
+			goto end;
+		}
+
+		status = efi_call_phys5(fh->open,
+				fh,
+				&h,
+				config_path,
+				EFI_FILE_MODE_READ, (u64)0);
+
+		if (status != EFI_SUCCESS)
+			goto end;
+
+		status = efi_call_phys4(h->get_info, h, &info_guid,
+					&info_sz, NULL);
+
+		if (status != EFI_BUFFER_TOO_SMALL)
+			goto close_config_file;
+
+		while (status == EFI_BUFFER_TOO_SMALL) {
+			status = efi_call_phys3(boottime->allocate_pool,
+					EFI_LOADER_DATA, info_sz, &info);
+
+			if (status != EFI_SUCCESS)
+				goto close_config_file;
+
+			status = efi_call_phys4(h->get_info, h, &info_guid,
+						&info_sz, info);
+
+			if (status == EFI_BUFFER_TOO_SMALL)
+				efi_call_phys1(boottime->free_pool, info);
+		}
+
+		if (status != EFI_SUCCESS)
+			goto free_config_file_info;
+
+		file_sz = info->file_size;
+
+		if (file_sz > hdr->cmdline_size)
+			file_sz = hdr->cmdline_size;
+
+		options_size = file_sz + 1;
+
+		status = low_alloc(options_size, 1, &cmdline);
+
+		if (status != EFI_SUCCESS)
+			goto free_config_file_info;
+
+		status = efi_call_phys3(h->read, h, &file_sz, cmdline);
+
+		if (status != EFI_SUCCESS)
+			goto free_config_file_cmdline;
+
+		*((u8 *)cmdline + file_sz) = 0;
+
+		goto free_config_file_info;
+free_config_file_cmdline:
+		low_free(options_size, cmdline);
+		cmdline = 0;
+		options_size = 0;
+free_config_file_info:
+		efi_call_phys1(boottime->free_pool, info);
+close_config_file:
+		efi_call_phys1(h->close, h);
+	}
+end:
 	hdr->cmd_line_ptr = cmdline;
 
 	hdr->ramdisk_image = 0;
 	hdr->ramdisk_size = 0;
 
-	status = handle_ramdisks(image, hdr);
+	status = handle_ramdisks(image, hdr, fh);
+
+	if (fh)
+		efi_call_phys1(fh->close, fh);
+
 	if (status != EFI_SUCCESS)
 		goto free_cmdline;

arch/x86/boot/compressed/eboot.h +2 -0

index 3925166..186b4c6 100644
@@ -20,6 +20,8 @@
 #define PIXEL_BLT_ONLY					3
 #define PIXEL_FORMAT_MAX				4
 
+#define CONFIG_FILE_NAME "linux.conf"
+
 struct efi_pixel_bitmask {
 	u32 red_mask;
 	u32 green_mask;

Signature · 1 line

1.7.9.4

Shea Levy

author

2012-03-20 22:22 UTC #2 lore raw

Quoted 12 lines · Shea Levy

Quoted 11 lines · Shea Levy
Hello,
Inlined is a patch to have the kernel read its parameters from a config file when booted via the EFI boot stub without any parameters passed. This patch roughly follows the plan I discussed when proposing this idea, except now the file is found relative to the location of the bzImage and there is no additional check to see if image->parent_handle is NULL (despite the spec saying it will be NULL when the image was loaded by the firmware itself, it was never NULL on any of the systems I tested).

Quoted 2 lines

Quoted 2 lines
Cheers,
Shea Levy

I haven't yet gotten a reply to this, should I wait until after the merge window and resubmit it then?

~Shea

H. Peter Anvin

reviewer

2012-03-20 22:24 UTC #3 lore raw

Quoted 13 lines · Shea Levy

Quoted 12 lines · Shea Levy
Quoted 11 lines · Shea Levy
Hello,
Inlined is a patch to have the kernel read its parameters from a config file when booted via the EFI boot stub without any parameters passed. This patch roughly follows the plan I discussed when proposing this idea, except now the file is found relative to the location of the bzImage and there is no additional check to see if image->parent_handle is NULL (despite the spec saying it will be NULL when the image was loaded by the firmware itself, it was never NULL on any of the systems I tested).

Quoted 6 lines

Quoted 2 lines
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Cheers,
Shea Levy
I haven't yet gotten a reply to this, should I wait until after the merge window and resubmit it then?

Yes, please.

-hpa

Matt Fleming

2012-05-31 15:41 UTC #4 lore raw

In reply to Shea Levy

Quoted 13 lines · Shea Levy

Quoted 12 lines · Shea Levy
Quoted 11 lines · Shea Levy
Hello,
Inlined is a patch to have the kernel read its parameters from a config file when booted via the EFI boot stub without any parameters passed. This patch roughly follows the plan I discussed when proposing this idea, except now the file is found relative to the location of the bzImage and there is no additional check to see if image->parent_handle is NULL (despite the spec saying it will be NULL when the image was loaded by the firmware itself, it was never NULL on any of the systems I tested).

Quoted 5 lines

Quoted 2 lines
Quoted 2 lines
Cheers,
Shea Levy
I haven't yet gotten a reply to this, should I wait until after the merge window and resubmit it then?

I'm wondering what use case you're catering for here that can't be handled with efibootmgr? What problem does this patch fix?

Shea Levy

author

2012-06-02 18:32 UTC #5 lore raw

Quoted 14 lines · Matt Fleming

Quoted 13 lines · Shea Levy
Quoted 12 lines · Shea Levy
Quoted 11 lines · Shea Levy
Hello,
Inlined is a patch to have the kernel read its parameters from a config file when booted via the EFI boot stub without any parameters passed. This patch roughly follows the plan I discussed when proposing this idea, except now the file is found relative to the location of the bzImage and there is no additional check to see if image->parent_handle is NULL (despite the spec saying it will be NULL when the image was loaded by the firmware itself, it was never NULL on any of the systems I tested).

Quoted 9 lines

Quoted 5 lines
Quoted 2 lines
Quoted 2 lines
Cheers,
Shea Levy
I haven't yet gotten a reply to this, should I wait until after the merge window and resubmit it then?
I'm wondering what use case you're catering for here that can't be handled with efibootmgr? What problem does this patch fix?

This fixes cases where efibootmgr doesn't work, either by design (in the case of removable boot media like a livecd) or due to firmware non-conformity (like VirtualBox's EFI emulation).

I had been waiting for the efi_printk stuff to get merged (for some reason I was under the impression it would be in 3.4) before submitting an updated version of this, and in the mean-time have been using the EDK shell + a startup.nsh file for the livecd case.