From a97756cbec448032f84b5bbfe4e101478d1e01e0 Mon Sep 17 00:00:00 2001 From: "Xin Li (Intel)" Date: Tue, 9 Jul 2024 08:40:48 -0700 Subject: x86/fred: Enable FRED right after init_mem_mapping() On 64-bit init_mem_mapping() relies on the minimal page fault handler provided by the early IDT mechanism. The real page fault handler is installed right afterwards into the IDT. This is problematic on CPUs which have X86_FEATURE_FRED set because the real page fault handler retrieves the faulting address from the FRED exception stack frame and not from CR2, but that does obviously not work when FRED is not yet enabled in the CPU. To prevent this enable FRED right after init_mem_mapping() without interrupt stacks. Those are enabled later in trap_init() after the CPU entry area is set up. [ tglx: Encapsulate the FRED details ] Fixes: 14619d912b65 ("x86/fred: FRED entry/exit and dispatch code") Reported-by: Hou Wenlong Suggested-by: Thomas Gleixner Signed-off-by: Xin Li (Intel) Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/20240709154048.3543361-4-xin@zytor.com --- arch/x86/include/asm/processor.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index a75a07f4931f..399f7d1c4c61 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -582,7 +582,8 @@ extern void switch_gdt_and_percpu_base(int); extern void load_direct_gdt(int); extern void load_fixmap_gdt(int); extern void cpu_init(void); -extern void cpu_init_exception_handling(void); +extern void cpu_init_exception_handling(bool boot_cpu); +extern void cpu_init_replace_early_idt(void); extern void cr4_init(void); extern void set_task_blockstep(struct task_struct *task, bool on); -- cgit v1.2.3