From df304c2d0dfd63c40561a8107a217e84fc3515e8 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Wed, 3 Mar 2021 13:49:26 +0000 Subject: [PATCH] arm64: cpufeatures: Fix handling of CONFIG_CMDLINE for idreg overrides The built-in kernel commandline (CONFIG_CMDLINE) can be configured in three different ways: 1. CMDLINE_FORCE: Use CONFIG_CMDLINE instead of any bootloader args 2. CMDLINE_EXTEND: Append the bootloader args to CONFIG_CMDLINE 3. CMDLINE_FROM_BOOTLOADER: Only use CONFIG_CMDLINE if there aren't any bootloader args. The early cmdline parsing to detect idreg overrides gets (2) and (3) slightly wrong: in the case of (2) the bootloader args are parsed first and in the case of (3) the CMDLINE is always parsed. Fix these issues by moving the bootargs parsing out into a helper function and following the same logic as that used by the EFI stub. Reviewed-by: Marc Zyngier Fixes: 33200303553d ("arm64: cpufeature: Add an early command-line cpufeature override facility") Link: https://lore.kernel.org/r/20210303134927.18975-2-will@kernel.org Signed-off-by: Will Deacon --- arch/arm64/kernel/idreg-override.c | 44 +++++++++++++++++------------- 1 file changed, 25 insertions(+), 19 deletions(-) diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index dffb16682330..cc071712c6f9 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -163,33 +163,39 @@ static __init void __parse_cmdline(const char *cmdline, bool parse_aliases) } while (1); } -static __init void parse_cmdline(void) +static __init const u8 *get_bootargs_cmdline(void) { - if (!IS_ENABLED(CONFIG_CMDLINE_FORCE)) { - const u8 *prop; - void *fdt; - int node; + const u8 *prop; + void *fdt; + int node; - fdt = get_early_fdt_ptr(); - if (!fdt) - goto out; + fdt = get_early_fdt_ptr(); + if (!fdt) + return NULL; - node = fdt_path_offset(fdt, "/chosen"); - if (node < 0) - goto out; + node = fdt_path_offset(fdt, "/chosen"); + if (node < 0) + return NULL; - prop = fdt_getprop(fdt, node, "bootargs", NULL); - if (!prop) - goto out; + prop = fdt_getprop(fdt, node, "bootargs", NULL); + if (!prop) + return NULL; - __parse_cmdline(prop, true); + return strlen(prop) ? prop : NULL; +} - if (!IS_ENABLED(CONFIG_CMDLINE_EXTEND)) - return; +static __init void parse_cmdline(void) +{ + const u8 *prop = get_bootargs_cmdline(); + + if (IS_ENABLED(CONFIG_CMDLINE_EXTEND) || + IS_ENABLED(CONFIG_CMDLINE_FORCE) || + !prop) { + __parse_cmdline(CONFIG_CMDLINE, true); } -out: - __parse_cmdline(CONFIG_CMDLINE, true); + if (!IS_ENABLED(CONFIG_CMDLINE_FORCE) && prop) + __parse_cmdline(prop, true); } /* Keep checkers quiet */ -- 2.20.1