From: Hugh Dickins Date: Wed, 2 Jul 2008 21:48:03 +0000 (+0100) Subject: x86: fix Intel Mac booting with EFI X-Git-Tag: v2.6.26-rc9~9^2~2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=216705d2720dedf630b55d641737f430ead0c228;p=linux-2.6 x86: fix Intel Mac booting with EFI Fedora reports that mem_init()'s zap_low_mappings(), extended to SMP in 61165d7a035f6571c7576e7f51e7230157724c8d x86: fix app crashes after SMP resume causes 32-bit Intel Mac machines to reboot very early when booting with EFI. The EFI code appears to manage low mappings for itself when needed; but like many before it, confuses PSE with PAE. So it has only been mapping half the space it needed when PSE but not PAE. This remained unnoticed until we moved the SMP zap_low_mappings() before efi_enter_virtual_mode(). Presumably could have been noticed years ago if anyone ran a UP kernel on such machines? Reported-by: Peter Jones Signed-off-by: Hugh Dickins Cc: Peter Jones Cc: Glauber Costa Cc: Andrew Morton Cc: Linus Torvalds Signed-off-by: Ingo Molnar Tested-by: Peter Jones --- diff --git a/arch/x86/kernel/efi_32.c b/arch/x86/kernel/efi_32.c index 5d23d85624..4b63c8e1f1 100644 --- a/arch/x86/kernel/efi_32.c +++ b/arch/x86/kernel/efi_32.c @@ -49,13 +49,13 @@ void efi_call_phys_prelog(void) local_irq_save(efi_rt_eflags); /* - * If I don't have PSE, I should just duplicate two entries in page - * directory. If I have PSE, I just need to duplicate one entry in + * If I don't have PAE, I should just duplicate two entries in page + * directory. If I have PAE, I just need to duplicate one entry in * page directory. */ cr4 = read_cr4(); - if (cr4 & X86_CR4_PSE) { + if (cr4 & X86_CR4_PAE) { efi_bak_pg_dir_pointer[0].pgd = swapper_pg_dir[pgd_index(0)].pgd; swapper_pg_dir[0].pgd = @@ -93,7 +93,7 @@ void efi_call_phys_epilog(void) cr4 = read_cr4(); - if (cr4 & X86_CR4_PSE) { + if (cr4 & X86_CR4_PAE) { swapper_pg_dir[pgd_index(0)].pgd = efi_bak_pg_dir_pointer[0].pgd; } else {