Commit-ID: c0b17b5bd4b7b98e7c6b67c9f69343b64711271b Gitweb: http://git.kernel.org/tip/c0b17b5bd4b7b98e7c6b67c9f69343b64711271b Author: Dave Hansen <[email protected]> AuthorDate: Fri, 12 Feb 2016 13:02:25 -0800 Committer: Ingo Molnar <[email protected]> CommitDate: Thu, 18 Feb 2016 19:46:29 +0100
x86/mm/pkeys: Dump PKRU with other kernel registers Protection Keys never affect kernel mappings. But, they can affect whether the kernel will fault when it touches a user mapping. The kernel doesn't touch user mappings without some careful choreography and these accesses don't generally result in oopses. But, if one does, we definitely want to have PKRU available so we can figure out if protection keys played a role. Signed-off-by: Dave Hansen <[email protected]> Reviewed-by: Thomas Gleixner <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Brian Gerst <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Denys Vlasenko <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/process_64.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index b9d99e0..776229e 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -116,6 +116,8 @@ void __show_regs(struct pt_regs *regs, int all) printk(KERN_DEFAULT "DR0: %016lx DR1: %016lx DR2: %016lx\n", d0, d1, d2); printk(KERN_DEFAULT "DR3: %016lx DR6: %016lx DR7: %016lx\n", d3, d6, d7); + if (boot_cpu_has(X86_FEATURE_OSPKE)) + printk(KERN_DEFAULT "PKRU: %08x\n", read_pkru()); } void release_thread(struct task_struct *dead_task)
