This is a note to let you know that I've just added the patch titled x86/microcode/AMD: Fix more fallout from CONFIG_RANDOMIZE_MEMORY=y to the 4.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: x86-microcode-amd-fix-more-fallout-from-config_randomize_memory-y.patch and it can be found in the queue-4.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 1c27f646b18fb56308dff82784ca61951bad0b48 Mon Sep 17 00:00:00 2001 From: Borislav Petkov <bp@xxxxxxx> Date: Thu, 27 Oct 2016 14:36:23 +0200 Subject: x86/microcode/AMD: Fix more fallout from CONFIG_RANDOMIZE_MEMORY=y From: Borislav Petkov <bp@xxxxxxx> commit 1c27f646b18fb56308dff82784ca61951bad0b48 upstream. We needed the physical address of the container in order to compute the offset within the relocated ramdisk. And we did this by doing __pa() on the virtual address. However, __pa() does checks whether the physical address is within PAGE_OFFSET and __START_KERNEL_map - see __phys_addr() - which fail if we have CONFIG_RANDOMIZE_MEMORY enabled: we feed a virtual address which *doesn't* have the randomization offset into a function which uses PAGE_OFFSET which *does* have that offset. This makes this check fire: VIRTUAL_BUG_ON((x > y) || !phys_addr_valid(x)); ^^^^^^ due to the randomization offset. The fix is as simple as using __pa_nodebug() because we do that randomization offset accounting later in that function ourselves. Reported-by: Bob Peterson <rpeterso@xxxxxxxxxx> Tested-by: Bob Peterson <rpeterso@xxxxxxxxxx> Signed-off-by: Borislav Petkov <bp@xxxxxxx> Cc: Andreas Gruenbacher <agruenba@xxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Brian Gerst <brgerst@xxxxxxxxx> Cc: Denys Vlasenko <dvlasenk@xxxxxxxxxx> Cc: H. Peter Anvin <hpa@xxxxxxxxx> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Steven Whitehouse <swhiteho@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: linux-mm <linux-mm@xxxxxxxxx> Link: http://lkml.kernel.org/r/20161027123623.j2jri5bandimboff@xxxxxxx Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/x86/kernel/cpu/microcode/amd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -429,7 +429,7 @@ int __init save_microcode_in_initrd_amd( * We need the physical address of the container for both bitness since * boot_params.hdr.ramdisk_image is a physical address. */ - cont = __pa(container); + cont = __pa_nodebug(container); cont_va = container; #endif Patches currently in stable-queue which might be from bp@xxxxxxx are queue-4.8/x86-microcode-amd-fix-more-fallout-from-config_randomize_memory-y.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html