The following commit has been merged into the x86/boot branch of tip: Commit-ID: 0c40b1c7a897bd9733e72aca2396fd3a62f1db17 Gitweb: https://git.kernel.org/tip/0c40b1c7a897bd9733e72aca2396fd3a62f1db17 Author: Borislav Petkov (AMD) <bp@xxxxxxxxx> AuthorDate: Mon, 08 Apr 2024 19:46:03 +02:00 Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx> CommitterDate: Mon, 27 May 2024 18:54:45 +02:00 x86/setup: Warn when option parsing is done too early Commit 4faa0e5d6d79 ("x86/boot: Move kernel cmdline setup earlier in the boot process (again)") fixed and issue where cmdline parsing would happen before the final boot_command_line string has been built from the builtin and boot cmdlines and thus cmdline arguments would get lost. Add a check to catch any future wrong use ordering so that such issues can be caught in time. Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Acked-by: Ingo Molnar <mingo@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240409152541.GCZhVd9XIPXyTNd9vc@fat_crate.local --- arch/x86/include/asm/setup.h | 8 ++++++++ arch/x86/kernel/setup.c | 2 ++ arch/x86/lib/cmdline.c | 8 ++++++++ 3 files changed, 18 insertions(+) diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h index e61e68d..0667b2a 100644 --- a/arch/x86/include/asm/setup.h +++ b/arch/x86/include/asm/setup.h @@ -28,6 +28,8 @@ #define NEW_CL_POINTER 0x228 /* Relative to real mode data */ #ifndef __ASSEMBLY__ +#include <linux/cache.h> + #include <asm/bootparam.h> #include <asm/x86_init.h> @@ -133,6 +135,12 @@ asmlinkage void __init __noreturn x86_64_start_reservations(char *real_mode_data #endif /* __i386__ */ #endif /* _SETUP */ +#ifdef CONFIG_CMDLINE_BOOL +extern bool builtin_cmdline_added __ro_after_init; +#else +#define builtin_cmdline_added 0 +#endif + #else /* __ASSEMBLY */ .macro __RESERVE_BRK name, size diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 05c5aa9..728927e 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -165,6 +165,7 @@ unsigned long saved_video_mode; static char __initdata command_line[COMMAND_LINE_SIZE]; #ifdef CONFIG_CMDLINE_BOOL static char __initdata builtin_cmdline[COMMAND_LINE_SIZE] = CONFIG_CMDLINE; +bool builtin_cmdline_added __ro_after_init; #endif #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE) @@ -765,6 +766,7 @@ void __init setup_arch(char **cmdline_p) strscpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE); } #endif + builtin_cmdline_added = true; #endif strscpy(command_line, boot_command_line, COMMAND_LINE_SIZE); diff --git a/arch/x86/lib/cmdline.c b/arch/x86/lib/cmdline.c index 80570eb..384da1f 100644 --- a/arch/x86/lib/cmdline.c +++ b/arch/x86/lib/cmdline.c @@ -6,8 +6,10 @@ #include <linux/kernel.h> #include <linux/string.h> #include <linux/ctype.h> + #include <asm/setup.h> #include <asm/cmdline.h> +#include <asm/bug.h> static inline int myisspace(u8 c) { @@ -205,12 +207,18 @@ __cmdline_find_option(const char *cmdline, int max_cmdline_size, int cmdline_find_option_bool(const char *cmdline, const char *option) { + if (IS_ENABLED(CONFIG_CMDLINE_BOOL)) + WARN_ON_ONCE(!builtin_cmdline_added); + return __cmdline_find_option_bool(cmdline, COMMAND_LINE_SIZE, option); } int cmdline_find_option(const char *cmdline, const char *option, char *buffer, int bufsize) { + if (IS_ENABLED(CONFIG_CMDLINE_BOOL)) + WARN_ON_ONCE(!builtin_cmdline_added); + return __cmdline_find_option(cmdline, COMMAND_LINE_SIZE, option, buffer, bufsize); }