diff options
| author | Thomas Gleixner | 2020-05-28 16:53:17 +0200 |
|---|---|---|
| committer | Thomas Gleixner | 2020-06-11 15:15:25 +0200 |
| commit | 94438af40d06c110988fc9e30baf801f38b1491a (patch) | |
| tree | f90a9a78e07fb7b4e466ed9798ed31d4565e2123 /arch | |
| parent | bdf5bde8aec7b53d0ea3a44d880a4e5106ff37f3 (diff) | |
x86/idt: Add comments about early #PF handling
The difference between 32 and 64 bit vs. early #PF handling is not
documented. Replace the FIXME at idt_setup_early_pf() with proper comments.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200528145522.807135882@linutronix.de
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kernel/idt.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/arch/x86/kernel/idt.c b/arch/x86/kernel/idt.c index 4b99f7bec384..5ef82fcf333d 100644 --- a/arch/x86/kernel/idt.c +++ b/arch/x86/kernel/idt.c @@ -61,7 +61,11 @@ static bool idt_setup_done __initdata; static const __initconst struct idt_data early_idts[] = { INTG(X86_TRAP_DB, asm_exc_debug), SYSG(X86_TRAP_BP, asm_exc_int3), + #ifdef CONFIG_X86_32 + /* + * Not possible on 64-bit. See idt_setup_early_pf() for details. + */ INTG(X86_TRAP_PF, asm_exc_page_fault), #endif }; @@ -256,8 +260,10 @@ void __init idt_setup_traps(void) * cpu_init() is invoked and sets up TSS. The IST variant is installed * after that. * - * FIXME: Why is 32bit and 64bit installing the PF handler at different - * places in the early setup code? + * Note, that X86_64 cannot install the real #PF handler in + * idt_setup_early_traps() because the memory intialization needs the #PF + * handler from the early_idt_handler_array to initialize the early page + * tables. */ void __init idt_setup_early_pf(void) { |