lkml.org 
[lkml]   [2021]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH v3 0/9] Parallel CPU bringup for x86_64


    On 21 December 2021 22:25:35 GMT, Tom Lendacky <thomas.lendacky@amd.com> wrote:
    >On 12/20/21 3:47 PM, Tom Lendacky wrote:
    >> On 12/20/21 3:29 PM, David Woodhouse wrote:
    >>> On Mon, 2021-12-20 at 12:54 -0600, Tom Lendacky wrote:
    >>>> Took the tree back to commit df9726cb7178 and then applied this change.
    >>>> I'm unable to trigger any kind of failure with this change.
    >>>
    >>> Hm... I fired up an EC2 m6a.48xlarge instance (192 CPUs) to play with.
    >>>
    >>> I can reproduce your triple-fault on SMP bringup, but only with kexec.
    >>> And I basically can't get *anything* to kexec without that triple-
    >>> fault. Not a clean 5.16-rc2, not the Fedora stock 5.14.10 kernel.
    >>>
    >>> If I *boot* instead of kexec, I have not yet seen the problem at all.
    >>> This is using Legacy BIOS not UEFI.
    >>
    >> Let me try with a legacy BIOS and see if I can repro. Might not be until
    >> tomorrow, though, since I had to let someone borrow the machine.
    >
    >I still encounter the issue using a legacy BIOS (SeaBIOS).

    I haven't had much time to play but have seen it with a stock kernel at least as far back as v5.0. They all triple-fault on bringing up secondary CPUs, on kexec.

    --
    Sent from my Android device with K-9 Mail. Please excuse my brevity.

    \
     
     \ /
      Last update: 2021-12-21 23:34    [W:2.789 / U:0.084 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site