From b8f2c21db390273c3eaf0e5308faeaeb1e233840 Mon Sep 17 00:00:00 2001 From: Nathan Zimmer Date: Tue, 8 Jan 2013 09:02:43 -0600 Subject: efi, x86: Pass a proper identity mapping in efi_call_phys_prelog Update efi_call_phys_prelog to install an identity mapping of all available memory. This corrects a bug on very large systems with more then 512 GB in which bios would not be able to access addresses above not in the mapping. The result is a crash that looks much like this. BUG: unable to handle kernel paging request at 000000effd870020 IP: [<0000000078bce331>] 0x78bce330 PGD 0 Oops: 0000 [#1] SMP Modules linked in: CPU 0 Pid: 0, comm: swapper/0 Tainted: G W 3.8.0-rc1-next-20121224-medusa_ntz+ #2 Intel Corp. Stoutland Platform RIP: 0010:[<0000000078bce331>] [<0000000078bce331>] 0x78bce330 RSP: 0000:ffffffff81601d28 EFLAGS: 00010006 RAX: 0000000078b80e18 RBX: 0000000000000004 RCX: 0000000000000004 RDX: 0000000078bcf958 RSI: 0000000000002400 RDI: 8000000000000000 RBP: 0000000078bcf760 R08: 000000effd870000 R09: 0000000000000000 R10: 0000000000000000 R11: 00000000000000c3 R12: 0000000000000030 R13: 000000effd870000 R14: 0000000000000000 R15: ffff88effd870000 FS: 0000000000000000(0000) GS:ffff88effe400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000effd870020 CR3: 000000000160c000 CR4: 00000000000006b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process swapper/0 (pid: 0, threadinfo ffffffff81600000, task ffffffff81614400) Stack: 0000000078b80d18 0000000000000004 0000000078bced7b ffff880078b81fff 0000000000000000 0000000000000082 0000000078bce3a8 0000000000002400 0000000060000202 0000000078b80da0 0000000078bce45d ffffffff8107cb5a Call Trace: [] ? on_each_cpu+0x77/0x83 [] ? change_page_attr_set_clr+0x32f/0x3ed [] ? efi_call4+0x46/0x80 [] ? efi_enter_virtual_mode+0x1f5/0x305 [] ? start_kernel+0x34a/0x3d2 [] ? repair_env_string+0x60/0x60 [] ? x86_64_start_reservations+0xba/0xc1 [] ? early_idt_handlers+0x120/0x120 [] ? x86_64_start_kernel+0x154/0x163 Code: Bad RIP value. RIP [<0000000078bce331>] 0x78bce330 RSP CR2: 000000effd870020 ---[ end trace ead828934fef5eab ]--- Cc: stable@vger.kernel.org Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Signed-off-by: Nathan Zimmer Signed-off-by: Robin Holt Signed-off-by: Matt Fleming --- arch/x86/platform/efi/efi_64.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) (limited to 'arch/x86/platform') diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index 95fd505dfeb6..2b2003860615 100644 --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -38,7 +38,7 @@ #include #include -static pgd_t save_pgd __initdata; +static pgd_t *save_pgd __initdata; static unsigned long efi_flags __initdata; static void __init early_code_mapping_set_exec(int executable) @@ -61,12 +61,20 @@ static void __init early_code_mapping_set_exec(int executable) void __init efi_call_phys_prelog(void) { unsigned long vaddress; + int pgd; + int n_pgds; early_code_mapping_set_exec(1); local_irq_save(efi_flags); - vaddress = (unsigned long)__va(0x0UL); - save_pgd = *pgd_offset_k(0x0UL); - set_pgd(pgd_offset_k(0x0UL), *pgd_offset_k(vaddress)); + + n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE); + save_pgd = kmalloc(n_pgds * sizeof(pgd_t), GFP_KERNEL); + + for (pgd = 0; pgd < n_pgds; pgd++) { + save_pgd[pgd] = *pgd_offset_k(pgd * PGDIR_SIZE); + vaddress = (unsigned long)__va(pgd * PGDIR_SIZE); + set_pgd(pgd_offset_k(pgd * PGDIR_SIZE), *pgd_offset_k(vaddress)); + } __flush_tlb_all(); } @@ -75,7 +83,11 @@ void __init efi_call_phys_epilog(void) /* * After the lock is released, the original page table is restored. */ - set_pgd(pgd_offset_k(0x0UL), save_pgd); + int pgd; + int n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE); + for (pgd = 0; pgd < n_pgds; pgd++) + set_pgd(pgd_offset_k(pgd * PGDIR_SIZE), save_pgd[pgd]); + kfree(save_pgd); __flush_tlb_all(); local_irq_restore(efi_flags); early_code_mapping_set_exec(0); -- cgit v1.2.1 From 712ba9e9afc4b3d3d6fa81565ca36fe518915c01 Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Fri, 25 Jan 2013 10:07:25 +0000 Subject: x86, efi: Set runtime_version to the EFI spec revision efi.runtime_version is erroneously being set to the value of the vendor's firmware revision instead of that of the implemented EFI specification. We can't deduce which EFI functions are available based on the revision of the vendor's firmware since the version scheme is likely to be unique to each vendor. What we really need to know is the revision of the implemented EFI specification, which is available in the EFI System Table header. Cc: Seiji Aguchi Cc: Matthew Garrett Cc: stable@vger.kernel.org # 3.7.x Signed-off-by: Matt Fleming --- arch/x86/platform/efi/efi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/platform') diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index ad4439145f85..35682489f6d6 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -941,7 +941,7 @@ void __init efi_enter_virtual_mode(void) * * Call EFI services through wrapper functions. */ - efi.runtime_version = efi_systab.fw_revision; + efi.runtime_version = efi_systab.hdr.revision; efi.get_time = virt_efi_get_time; efi.set_time = virt_efi_set_time; efi.get_wakeup_time = virt_efi_get_wakeup_time; -- cgit v1.2.1