On Wed, Mar 23, 2022 at 11:47:08PM -0700, KernelCI bot wrote:
The KernelCI bisection bot has identified commit 5949965ec9340cfc0e
("x86/PCI: Preserve host bridge windows completely covered by E820")
as causing a boot regression in next on asus-C523NA-A20057-coral (a
Chromebook AIUI). Unfortunately there's no useful output when starting
the kernel. I've left the full report below including links to the web
dashboard.
The last successful boot in -next had this log:
https://storage.kernelci.org/next/master/next-20220310/x86_64/x86_64_defconfig+x86-chromebook/gcc-10/lab-collabora/baseline-asus-C523NA-A20057-coral.html
I'd also note that the machine hp-x360-12b-n4000-octopus appears to have
started failing at the same time with similar symptoms, failing log:
https://storage.kernelci.org/next/master/next-20220324/x86_64/x86_64_defconfig+x86-chromebook/gcc-10/lab-collabora/baseline-hp-x360-12b-n4000-octopus.html
and passing log:
https://storage.kernelci.org/next/master/next-20220310/x86_64/x86_64_defconfig+x86-chromebook/gcc-10/lab-collabora/baseline-hp-x360-12b-n4000-octopus.html
though we didn't get a bisect for that yet. That's also a Chromebook.
> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
> * This automated bisection report was sent to you on the basis *
> * that you may be involved with the breaking commit it has *
> * found. No manual investigation has been done to verify it, *
> * and the root cause of the problem may be somewhere else. *
> * *
> * If you do send a fix, please include this trailer: *
> * Reported-by: "kernelci.org bot" <bot@xxxxxxxxxxxx> *
> * *
> * Hope this helps! *
> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
>
> next/master bisection: baseline.login on asus-C523NA-A20057-coral
>
> Summary:
> Start: f8833a2b2356 Add linux-next specific files for 20220322
> Plain log: https://storage.kernelci.org/next/master/next-20220322/x86_64/x86_64_defconfig+x86-chromebook/gcc-10/lab-collabora/baseline-asus-C523NA-A20057-coral.txt
> HTML log: https://storage.kernelci.org/next/master/next-20220322/x86_64/x86_64_defconfig+x86-chromebook/gcc-10/lab-collabora/baseline-asus-C523NA-A20057-coral.html
> Result: 5949965ec934 x86/PCI: Preserve host bridge windows completely covered by E820
>
> Checks:
> revert: PASS
> verify: PASS
>
> Parameters:
> Tree: next
> URL: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
> Branch: master
> Target: asus-C523NA-A20057-coral
> CPU arch: x86_64
> Lab: lab-collabora
> Compiler: gcc-10
> Config: x86_64_defconfig+x86-chromebook
> Test case: baseline.login
>
> Breaking commit found:
>
> -------------------------------------------------------------------------------
> commit 5949965ec9340cfc0e65f7d8a576b660b26e2535
> Author: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Date: Thu Mar 3 18:03:30 2022 -0600
>
> x86/PCI: Preserve host bridge windows completely covered by E820
>
> Many folks have reported PCI devices not working. It could affect any
> device, but most reports are for Thunderbolt controllers on Lenovo Yoga and
> Clevo Barebone laptops and the touchpad on Lenovo IdeaPads.
>
> In every report, a region in the E820 table entirely encloses a PCI host
> bridge window from _CRS, and because of 4dc2287c1805 ("x86: avoid E820
> regions when allocating address space"), we ignore the entire window,
> preventing us from assigning space to PCI devices.
>
> For example, the dmesg log [2] from bug report [1] shows:
>
> BIOS-e820: [mem 0x000000004bc50000-0x00000000cfffffff] reserved
> pci_bus 0000:00: root bus resource [mem 0x65400000-0xbfffffff window]
> pci 0000:00:15.0: BAR 0: no space for [mem size 0x00001000 64bit]
>
> The efi=debug dmesg log [3] from the same report shows the EFI memory map
> entries that created the E820 map:
>
> efi: mem47: [Reserved | |WB|WT|WC|UC] range=[0x4bc50000-0x5fffffff]
> efi: mem48: [Reserved | |WB| | |UC] range=[0x60000000-0x60ffffff]
> efi: mem49: [Reserved | | | | | ] range=[0x61000000-0x653fffff]
> efi: mem50: [MMIO |RUN| | | |UC] range=[0x65400000-0xcfffffff]
>
> 4dc2287c1805 ("x86: avoid E820 regions when allocating address space")
> works around issues where _CRS contains non-window address space that can't
> be used for PCI devices. It does this by removing E820 regions from host
> bridge windows. But in these reports, the E820 region covers the entire
> window, so 4dc2287c1805 makes it completely unusable.
>
> Per UEFI v2.8, sec 7.2, the EfiMemoryMappedIO type means:
>
> Used by system firmware to request that a memory-mapped IO region be
> mapped by the OS to a virtual address so it can be accessed by EFI
> runtime services.
>
> A host bridge window is definitely a memory-mapped IO region, and EFI
> runtime services may need to access it, so I don't think we can argue that
> this is a firmware defect.
>
> Instead, change the 4dc2287c1805 strategy so it only removes E820 regions
> when they overlap *part* of a host bridge window on the assumption that a
> partial overlap is really register space, not part of the window proper.
>
> If an E820 region covers the entire window from _CRS, assume the _CRS
> window is correct and do nothing.
>
> [1] https://bugzilla.redhat.com/show_bug.cgi?id=1868899
> [2] https://bugzilla.redhat.com/attachment.cgi?id=1711424
> [3] https://bugzilla.redhat.com/attachment.cgi?id=1861407
>
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=206459
> BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=214259
> BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1868899
> BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1871793
> BugLink: https://bugs.launchpad.net/bugs/1878279
> BugLink: https://bugs.launchpad.net/bugs/1931715
> BugLink: https://bugs.launchpad.net/bugs/1932069
> BugLink: https://bugs.launchpad.net/bugs/1921649
> Fixes: 4dc2287c1805 ("x86: avoid E820 regions when allocating address space")
> Link: https://lore.kernel.org/r/20220228105259.230903-1-hdegoede@xxxxxxxxxx
> Based-on-patch-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> Link: https://lore.kernel.org/r/20220304035110.988712-4-helgaas@xxxxxxxxxx
> Reported-by: Benoit Grégoire <benoitg@xxxxxxxx> # BZ 206459
> Reported-by: wse@xxxxxxxxxxxxxxxxxxx # BZ 214259
> Tested-by: Matt Hansen <2lprbe78@xxxxxxxx>
> Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> diff --git a/arch/x86/kernel/resource.c b/arch/x86/kernel/resource.c
> index 7378ea146976..90203217c359 100644
> --- a/arch/x86/kernel/resource.c
> +++ b/arch/x86/kernel/resource.c
> @@ -39,6 +39,21 @@ void remove_e820_regions(struct device *dev, struct resource *avail)
> e820_start = entry->addr;
> e820_end = entry->addr + entry->size - 1;
>
> + /*
> + * If an E820 entry covers just part of the resource, we
> + * assume E820 is telling us about something like host
> + * bridge register space that is unavailable for PCI
> + * devices. But if it covers the *entire* resource, it's
> + * more likely just telling us that this is MMIO space, and
> + * that doesn't need to be removed.
> + */
> + if (e820_start <= avail->start && avail->end <= e820_end) {
> + dev_info(dev, "resource %pR fully covered by e820 entry [mem %#010Lx-%#010Lx]\n",
> + avail, e820_start, e820_end);
> +
> + continue;
> + }
> +
> resource_clip(avail, e820_start, e820_end);
> if (orig.start != avail->start || orig.end != avail->end) {
> dev_info(dev, "clipped %pR to %pR for e820 entry [mem %#010Lx-%#010Lx]\n",
> -------------------------------------------------------------------------------
>
>
> Git bisection log:
>
> -------------------------------------------------------------------------------
> git bisect start
> # good: [5628b8de1228436d47491c662dc521bc138a3d43] Merge tag 'random-5.18-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random
> git bisect good 5628b8de1228436d47491c662dc521bc138a3d43
> # bad: [f8833a2b23562be2dae91775127c8014c44d8566] Add linux-next specific files for 20220322
> git bisect bad f8833a2b23562be2dae91775127c8014c44d8566
> # bad: [d2de72259f3d22054272217eac92e624835bfc3b] Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git
> git bisect bad d2de72259f3d22054272217eac92e624835bfc3b
> # bad: [5920db3e4b50218dcf2101f3d87c3b69a1120981] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git
> git bisect bad 5920db3e4b50218dcf2101f3d87c3b69a1120981
> # bad: [b579dc07dce4637b7f2a3fb84394ebbd6666a81f] Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git
> git bisect bad b579dc07dce4637b7f2a3fb84394ebbd6666a81f
> # bad: [b5475dd9fab03e6867abad00ecb98e0d3827ad31] Merge branch 'for-next' of git://git.armlinux.org.uk/~rmk/linux-arm.git
> git bisect bad b5475dd9fab03e6867abad00ecb98e0d3827ad31
> # good: [7b72f3bb0907319e15765ae9dcf1f15fdd112bcf] Merge remote-tracking branch 'asoc/for-5.17' into asoc-linus
> git bisect good 7b72f3bb0907319e15765ae9dcf1f15fdd112bcf
> # bad: [077dc6bc0658177057bfd69ef3a990e6d8d32146] Merge branch 'gpio/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
> git bisect bad 077dc6bc0658177057bfd69ef3a990e6d8d32146
> # good: [fd11727eec0dd95ee1b7d8f9f10ee60678eecc29] crypto: hisilicon/qm - fix memset during queues clearing
> git bisect good fd11727eec0dd95ee1b7d8f9f10ee60678eecc29
> # good: [646b907e1559f006c79a752ee3eebe220ceb983d] Merge tag 'asoc-v5.18' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
> git bisect good 646b907e1559f006c79a752ee3eebe220ceb983d
> # bad: [f8ed0b7c999405bd12ab9ebb0765e2baa7eb6184] Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci.git
> git bisect bad f8ed0b7c999405bd12ab9ebb0765e2baa7eb6184
> # good: [9fd75b66b8f68498454d685dc4ba13192ae069b0] ax25: Fix refcount leaks caused by ax25_cb_del()
> git bisect good 9fd75b66b8f68498454d685dc4ba13192ae069b0
> # good: [3fd177beee75eb2d7e5b19992e8c90eb1a141432] Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git
> git bisect good 3fd177beee75eb2d7e5b19992e8c90eb1a141432
> # good: [09005bef55291a99b491a47ce676dfb4f40f8edd] Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git
> git bisect good 09005bef55291a99b491a47ce676dfb4f40f8edd
> # good: [d13f73e9108a75209d03217d60462f51092499fe] x86/PCI: Log host bridge window clipping for E820 regions
> git bisect good d13f73e9108a75209d03217d60462f51092499fe
> # bad: [5949965ec9340cfc0e65f7d8a576b660b26e2535] x86/PCI: Preserve host bridge windows completely covered by E820
> git bisect bad 5949965ec9340cfc0e65f7d8a576b660b26e2535
> # first bad commit: [5949965ec9340cfc0e65f7d8a576b660b26e2535] x86/PCI: Preserve host bridge windows completely covered by E820
> -------------------------------------------------------------------------------
>
>
> -=-=-=-=-=-=-=-=-=-=-=-
> Groups.io Links: You receive all messages sent to this group.
> View/Reply Online (#25006): https://groups.io/g/kernelci-results/message/25006
> Mute This Topic: https://groups.io/mt/89994186/1131744
> Group Owner: kernelci-results+owner@xxxxxxxxx
> Unsubscribe: https://groups.io/g/kernelci-results/unsub [broonie@xxxxxxxxxx]
> -=-=-=-=-=-=-=-=-=-=-=-
>
>
Attachment:
signature.asc
Description: PGP signature
