From f6cff820877ff34839920ff9de9b912359cfb607 Mon Sep 17 00:00:00 2001 From: Hamza Mahfooz Date: Tue, 23 Jun 2026 11:24:29 -0400 Subject: [PATCH] x86/build: Only align ENTRY_TEXT to PMD_SIZE if necessary PTI requires the begin and end of ENTRY_TEXT be aligned to PMD_SIZE. SRSO requires srso_alias_untrain_ret to be 2M aligned. This costs between 2-4 MiB of RAM (depending on the size of the preceding section). So, only align when either of the two are enabled. Co-developed-by: Jared White Signed-off-by: Jared White Signed-off-by: Hamza Mahfooz Signed-off-by: Borislav Petkov (AMD) Signed-off-by: Ingo Molnar Link: https://patch.msgid.link/20260623152430.1473481-1-hamzamahfooz@linux.microsoft.com --- arch/x86/kernel/vmlinux.lds.S | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kernel/vmlinux.lds.S b/arch/x86/kernel/vmlinux.lds.S index 74e336d7f9dd..10caf92d075d 100644 --- a/arch/x86/kernel/vmlinux.lds.S +++ b/arch/x86/kernel/vmlinux.lds.S @@ -65,8 +65,14 @@ const_cpu_current_top_of_stack = cpu_current_top_of_stack; __end_rodata_hpage_align = .; \ __end_rodata_aligned = .; +#if defined(CONFIG_MITIGATION_PAGE_TABLE_ISOLATION) || defined(CONFIG_MITIGATION_SRSO) #define ALIGN_ENTRY_TEXT_BEGIN . = ALIGN(PMD_SIZE); #define ALIGN_ENTRY_TEXT_END . = ALIGN(PMD_SIZE); +#else +#define ALIGN_ENTRY_TEXT_BEGIN +#define ALIGN_ENTRY_TEXT_END +#endif + #else #define X86_ALIGN_RODATA_BEGIN