@@ -13,6 +13,7 @@
#include <linux/efi.h>
#include <linux/kernel.h>
#include <linux/printk.h> /* For CONSOLE_LOGLEVEL_* */
+#include <linux/cmdline.h>
#include <asm/efi.h>
#include <asm/setup.h>
@@ -172,6 +173,34 @@ int efi_printk(const char *fmt, ...)
return printed;
}
+/**
+ * efi_handle_cmdline() - handle adding in building parts of the command line
+ * @cmdline: kernel command line
+ *
+ * Add in the generic parts of the commandline and start the parsing of the
+ * command line.
+ *
+ * Return: status code
+ */
+efi_status_t efi_handle_cmdline(char const *cmdline)
+{
+ efi_status_t status = EFI_SUCCESS;
+
+ if (sizeof(CMDLINE_STATIC_PREPEND) > 1)
+ status |= efi_parse_options(CMDLINE_STATIC_PREPEND);
+
+ if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE))
+ status |= efi_parse_options(cmdline);
+
+ if (sizeof(CMDLINE_STATIC_APPEND) > 1)
+ status |= efi_parse_options(CMDLINE_STATIC_APPEND);
+
+ if (status != EFI_SUCCESS)
+ efi_err("Failed to parse options\n");
+
+ return status;
+}
+
/**
* efi_parse_options() - Parse EFI command line options
* @cmdline: kernel command line
@@ -172,6 +172,14 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
goto fail;
}
+#ifdef CONFIG_GENERIC_CMDLINE
+ status = efi_handle_cmdline(cmdline_ptr);
+ if (status != EFI_SUCCESS) {
+ goto fail_free_cmdline;
+ }
+#endif
+
+#ifdef CONFIG_CMDLINE
if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) ||
IS_ENABLED(CONFIG_CMDLINE_FORCE) ||
cmdline_size == 0) {
@@ -189,6 +197,7 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
goto fail_free_cmdline;
}
}
+#endif
efi_info("Booting Linux Kernel...\n");
@@ -800,6 +800,7 @@ efi_status_t efi_relocate_kernel(unsigned long *image_addr,
unsigned long alignment,
unsigned long min_addr);
+efi_status_t efi_handle_cmdline(char const *cmdline);
efi_status_t efi_parse_options(char const *cmdline);
void efi_parse_option_graphics(char *option);
@@ -673,6 +673,8 @@ unsigned long efi_main(efi_handle_t handle,
unsigned long bzimage_addr = (unsigned long)startup_32;
unsigned long buffer_start, buffer_end;
struct setup_header *hdr = &boot_params->hdr;
+ unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr |
+ ((u64)boot_params->ext_cmd_line_ptr << 32));
efi_status_t status;
efi_system_table = sys_table_arg;
@@ -735,6 +737,14 @@ unsigned long efi_main(efi_handle_t handle,
image_offset = 0;
}
+#ifdef CONFIG_GENERIC_CMDLINE
+ status = efi_handle_cmdline((char *)cmdline_paddr);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to parse options\n");
+ goto fail;
+ }
+#else /* CONFIG_GENERIC_CMDLINE */
+
#ifdef CONFIG_CMDLINE_BOOL
status = efi_parse_options(CONFIG_CMDLINE);
if (status != EFI_SUCCESS) {
@@ -743,8 +753,6 @@ unsigned long efi_main(efi_handle_t handle,
}
#endif
if (!IS_ENABLED(CONFIG_CMDLINE_OVERRIDE)) {
- unsigned long cmdline_paddr = ((u64)hdr->cmd_line_ptr |
- ((u64)boot_params->ext_cmd_line_ptr << 32));
status = efi_parse_options((char *)cmdline_paddr);
if (status != EFI_SUCCESS) {
efi_err("Failed to parse options\n");
@@ -752,6 +760,7 @@ unsigned long efi_main(efi_handle_t handle,
}
}
+#endif
/*
* At this point, an initrd may already have been loaded by the
* bootloader and passed via bootparams. We permit an initrd loaded
This adds code to handle the generic command line changes. The efi code appears that it doesn't benefit as much from this design as it could. For example, if you had a prepend command line with "nokaslr" then you might be helpful to re-enable it in the boot loader or dts, but there appears to be no way to re-enable kaslr or some of the other options. The efi command line handling is incorrect. x86 and arm have an append system however the efi code prepends the command line. For example, you could have a non-upgradable bios which sends efi=disable_early_pci_dma This hypothetically could have been set because early pci dma caused issues on early versions of the product. Then later the early pci dma was made to work and the company desired to start using it. To override the bios you could set the CONFIG_CMDLINE to, efi=no_disable_early_pci_dma then parsing would normally start with the bios command line, then move to the CONFIG_CMDLINE and you would end up with early pci dma turned on. however, current efi code keeps early pci dma off because the bios arguments always override the built in. Per my reading this is different from the main body of x86, arm, and arm64. The generic command line provides both append and prepend, so it alleviates this issue if it's used. However not all architectures use it. It would be desirable to allow the efi stub to have it's builtin command line to be modified after compile, but I don't see a feasible way to do that currently. Cc: xe-linux-external@cisco.com Signed-off-by: Daniel Walker <danielwa@cisco.com> --- .../firmware/efi/libstub/efi-stub-helper.c | 29 +++++++++++++++++++ drivers/firmware/efi/libstub/efi-stub.c | 9 ++++++ drivers/firmware/efi/libstub/efistub.h | 1 + drivers/firmware/efi/libstub/x86-stub.c | 13 +++++++-- 4 files changed, 50 insertions(+), 2 deletions(-)