New regression in v5.19-rc1.
----- Forwarded message from [email protected] -----
Subject: [Bug 216109] New: Steam Deck fails to boot when E820 entries clipped
out of _CRS
https://bugzilla.kernel.org/show_bug.cgi?id=216109
Summary: Steam Deck fails to boot when E820 entries clipped out
of _CRS
Kernel Version: v5.19
Guilherme G. Piccoli reported that v5.18 boots fine on Steam Deck, but
v5.19-rc1 does not. He bisected it to 4c5e242d3e93 ("x86/PCI: Clip only host
bridge windows for E820 regions") [1].
A quirk similar to [2] that disables E820 clipping makes v5.19-rc1 work again.
The reason why v5.18 (which always does E820 clipping by default) works, while
v5.19-rc1 (which also does E820 clipping on this platform) does not has not
been explained yet.
[1] https://git.kernel.org/linus/4c5e242d3e93
[2] https://git.kernel.org/linus/d341838d776a
----- End forwarded message -----
Hi,
On 6/10/22 00:43, Bjorn Helgaas wrote:
> New regression in v5.19-rc1.
>
> ----- Forwarded message from [email protected] -----
>
> Subject: [Bug 216109] New: Steam Deck fails to boot when E820 entries clipped
> out of _CRS
>
> https://bugzilla.kernel.org/show_bug.cgi?id=216109
>
> Summary: Steam Deck fails to boot when E820 entries clipped out
> of _CRS
> Kernel Version: v5.19
>
> Guilherme G. Piccoli reported that v5.18 boots fine on Steam Deck, but
> v5.19-rc1 does not. He bisected it to 4c5e242d3e93 ("x86/PCI: Clip only host
> bridge windows for E820 regions") [1].
>
> A quirk similar to [2] that disables E820 clipping makes v5.19-rc1 work again.
>
> The reason why v5.18 (which always does E820 clipping by default) works, while
> v5.19-rc1 (which also does E820 clipping on this platform) does not has not
> been explained yet.
>
> [1] https://git.kernel.org/linus/4c5e242d3e93
> [2] https://git.kernel.org/linus/d341838d776a
>
> ----- End forwarded message -----
I've added some analysis of the logs to the bug. Summary: I think we may
need to revert 4c5e242d3e93, this will be a non trivial revert moving
the pci_use_e820 check added in later commits to arch_remove_reservations().
See the bug for details and lets discuss this further in the bug.
In case we do eventually decide to go with a revert, I'll prepare
a revert later today and push it to:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans
Note I do NOT plan to merge this through the pdx86 tree, the reason
to put it there is to get the builders to play with it, since in the
past: https://lore.kernel.org/linux-pci/[email protected]/
we had some build issues with the check inside arch_remove_reservations().
Regards,
Hans
[TLDR: I'm adding this regression report to the list of tracked
regressions; all text from me you find below is based on a few templates
paragraphs you might have encountered already already in similar form.]
Hi, this is your Linux kernel regression tracker.
On 10.06.22 00:43, Bjorn Helgaas wrote:
> New regression in v5.19-rc1.
>
> ----- Forwarded message from [email protected] -----
>
> Subject: [Bug 216109] New: Steam Deck fails to boot when E820 entries clipped
> out of _CRS
>
> https://bugzilla.kernel.org/show_bug.cgi?id=216109
>
> Summary: Steam Deck fails to boot when E820 entries clipped out
> of _CRS
> Kernel Version: v5.19
>
> Guilherme G. Piccoli reported that v5.18 boots fine on Steam Deck, but
> v5.19-rc1 does not. He bisected it to 4c5e242d3e93 ("x86/PCI: Clip only host
> bridge windows for E820 regions") [1].
>
> A quirk similar to [2] that disables E820 clipping makes v5.19-rc1 work again.
>
> The reason why v5.18 (which always does E820 clipping by default) works, while
> v5.19-rc1 (which also does E820 clipping on this platform) does not has not
> been explained yet.
>
> [1] https://git.kernel.org/linus/4c5e242d3e93
> [2] https://git.kernel.org/linus/d341838d776a
To be sure below issue doesn't fall through the cracks unnoticed, I'm
adding it to regzbot, my Linux kernel regression tracking bot:
#regzbot ^introduced 4c5e242d3e93
#regzbot title x86/PCI/e820:Steam Deck fails to boot when E820 entries
clipped out of _CRS
#regzbot ignore-activity
#regzbot link: https://bugzilla.kernel.org/show_bug.cgi?id=216109
This isn't a regression? This issue or a fix for it are already
discussed somewhere else? It was fixed already? You want to clarify when
the regression started to happen? Or point out I got the title or
something else totally wrong? Then just reply -- ideally with also
telling regzbot about it, as explained here:
https://linux-regtracking.leemhuis.info/tracked-regression/
Reminder for developers: When fixing the issue, add 'Link:' tags
pointing to the report (the mail this one replied to), as the kernel's
documentation call for; above page explains why this is important for
tracked regressions.
Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
P.S.: As the Linux kernel's regression tracker I deal with a lot of
reports and sometimes miss something important when writing mails like
this. If that's the case here, don't hesitate to tell me in a public
reply, it's in everyone's interest to set the public record straight.
TWIMC: this mail is primarily send for documentation purposes and for
regzbot, my Linux kernel regression tracking bot. These mails usually
contain '#forregzbot' in the subject, to make them easy to spot and filter.
On 12.06.22 13:11, Thorsten Leemhuis wrote:
>> Subject: [Bug 216109] New: Steam Deck fails to boot when E820 entries clipped
>> out of _CRS
>>
>> https://bugzilla.kernel.org/show_bug.cgi?id=216109
#regzbot fixed-by: a2b36ffbf5b6
Ciao, Thorsten (wearing his 'the Linux kernel's regression tracker' hat)
P.S.: As the Linux kernel's regression tracker I deal with a lot of
reports and sometimes miss something important when writing mails like
this. If that's the case here, don't hesitate to tell me in a public
reply, it's in everyone's interest to set the public record straight.