From: Dave Young <dyoung@redhat.com>
To: Matthew Garrett <mjg59@google.com>
Cc: linux-efi <linux-efi@vger.kernel.org>,
Ard Biesheuvel <ard.biesheuvel@linaro.org>,
kexec@lists.infradead.org,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
bhsharma@redhat.com
Subject: Re: [PATCH] do not clean dummy variable in kexec path
Date: Tue, 6 Aug 2019 10:44:13 +0800 [thread overview]
Message-ID: <20190806024413.GB6956@dhcp-128-65.nay.redhat.com> (raw)
In-Reply-To: <CACdnJusRUnhmOLdowqbGoM9Z-tWsKrhZ8sFfQUUmjyKmRVN+vw@mail.gmail.com>
On 08/05/19 at 10:09am, Matthew Garrett wrote:
> On Mon, Aug 5, 2019 at 1:36 AM Dave Young <dyoung@redhat.com> wrote:
> >
> > kexec reboot fails randomly in UEFI based kvm guest. The firmware
> > just reset while calling efi_delete_dummy_variable(); Unfortunately
> > I don't know how to debug the firmware, it is also possible a potential
> > problem on real hardware as well although nobody reproduced it.
> >
> > The intention of efi_delete_dummy_variable is to trigger garbage collection
> > when entering virtual mode. But SetVirtualAddressMap can only run once
> > for each physical reboot, thus kexec_enter_virtual_mode is not necessarily
> > a good place to clean dummy object.
>
> I agree that this isn't necessarily the best place to do this in the
> kexec case, but given we control the firmware, figuring out what's
> actually breaking seems like a good plan.
I'm more than glad to get the root cause, if you can help on debugging I
would like to share the efi var file etc.
But it is indeed a problem cause weird reset on end user part, but even if we can
not find the root cause (in firmware..) I think we still need avoid it
with such workaround.
Thanks
Dave
prev parent reply other threads:[~2019-08-06 2:44 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-05 8:35 [PATCH] do not clean dummy variable in kexec path Dave Young
2019-08-05 15:55 ` Ard Biesheuvel
2019-08-06 2:41 ` Dave Young
2019-08-08 7:49 ` Dave Young
2019-08-05 17:09 ` Matthew Garrett
2019-08-06 2:44 ` Dave Young [this message]
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