lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Mon, 23 Jan 2017 10:01:53 -0800
From:   "Luck, Tony" <>
To:     Borislav Petkov <>
Cc:,,,, Ingo Molnar <>,
        Dave Young <>,
        Prarit Bhargava <>,
        Junichi Nomura <>,
        Kiyoshi Ueda <>,
        Naoya Horiguchi <>
Subject: Re: [PATCH] x86/mce: Keep quiet in case of broadcasted mce after
 system panic

On Mon, Jan 23, 2017 at 06:51:30PM +0100, Borislav Petkov wrote:
> Hey Tony,
> a "welcome back" is in order? :-)

Yes - first day back today. Lots of catching up to do.

> And apparently crash knows about poisoned pages and handles them:
> static int __init crash_save_vmcoreinfo_init(void)
> {
> 	...
>         VMCOREINFO_NUMBER(PG_hwpoison);
> #endif
> so if that works, the kexeced kernel should know about that list.

Oh good ... it is smarter than I thought.

> Doesn't matter, right? The new copy is as clueless as the old one about
> those MCEs.

If things are well enough initialized that we don't reset, and
get to do_machine_check(), then this code from Ashok:

        /* If this CPU is offline, just bail out. */
        if (cpu_is_offline(smp_processor_id())) {
                u64 mcgstatus;

                mcgstatus = mce_rdmsrl(MSR_IA32_MCG_STATUS);
                if (mcgstatus & MCG_STATUS_RIPV) {
                        mce_wrmsrl(MSR_IA32_MCG_STATUS, 0);

will ignore the machine check on the other cpus ... assuming
that "cpu_is_offline(smp_processor_id())" does the right thing
in the kexec case where this is an "old" cpu that isn't online
in the new kernel.


Powered by blists - more mailing lists