Re: [BUG] GPF on reboot of box

From: Steven Rostedt
Date: Fri Oct 06 2017 - 23:13:26 EST

This bug still crashes my box on rc3

-- Steve

On October 6, 2017 10:21:26 PM EDT, Nadav Amit <nadav.amit@xxxxxxxxx> wrote:
>Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>> Starting with v4.14-rc1 my box crashes during a reboot. All I get is
>> the following:
>> [ 250.615793] sd 0:0:0:0: [sda] Synchronizing SCSI cache
>> [ 250.635639] reboot: Restarting system
>> [ 250.639671] reboot: machine restart
>> [ 250.643842] general protection fault: 0000 [#1] PREEMPT SMP KASAN
>> Then nothing. No reboot, it just hangs there.
>> I bisected it down to this commit:
>> 660da7c9228f ("x86/mm: Enable CR4.PCIDE on supported systems")
>> If I comment out the setting of X86_CR4_PCIDE in that commit, it
>> fine. But...
>> I noticed that commit c7ad5ad29 ("x86/mm/64: Initialize CR4.PCIDE
>> early") moved the problem code from arch/x86/kernel/cpu/common.c to
>> arch/x86/mm/init.c
>> If I comment it out in v4.14-rc1, it crashes on boot up.
>> It appears that my box doesn't like having X86_CR4_PCIDE set. it
>> reboot to fail. But it also appears that setting that is required for
>> some other code to work.
>IIRC, there was a problem in rc1, which should be resolved in newer
>If you need to run rc1, you can try to use the kernel parameter

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