On Sat, 15 Mar 2025 at 00:28, Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>
> On Fri, Mar 14, 2025 at 07:10:58AM +0000, Zhangfei Gao wrote:
> > "bcb81ac6ae3c iommu: Get DT/ACPI parsing into the proper probe path"
> > changes arm_smmu_probe_device sequence.
>
> Normal commit reference style is:
>
> bcb81ac6ae3c ("iommu: Get DT/ACPI parsing into the proper probe path")
>
> bcb81ac6ae3c is not a valid upstream commit. It does appear in
> next-20250314, incorporated via f5a5f66e2791 ("Merge branches
> 'apple/dart', 'arm/smmu/updates', 'arm/smmu/bindings', 's390', 'core',
> 'intel/vt-d' and 'amd/amd-vi' into next") from
> git://git.kernel.org/pub/scm/linux/kernel/git/iommu/linux.git.
>
> I think there's some value in keeping fixes close to whatever needs to
> be fixed, so since bcb81ac6ae3c came via the iommu tree, I would tend
> to merge the fix the same way.
OK, understand.
Then would you mind give an ack.
>
> Unless there's a rebase to merge this change before bcb81ac6ae3c, this
> probably needs a "Fixes:" tag so people who backport bcb81ac6ae3c have
> a hint that this quirk change should be backported along with it.
>
> > From
> > pci_bus_add_device(virtfn)
> > -> pci_fixup_device(pci_fixup_final, dev)
> > -> arm_smmu_probe_device
> >
> > To
> > pci_device_add(virtfn, virtfn->bus)
> > -> pci_fixup_device(pci_fixup_header, dev)
> > -> arm_smmu_probe_device
>
> This doesn't include enough detail to show the change. I don't know
> the path to arm_smmu_probe_device() and how it relates to
> pci_bus_add_device() and pci_device_add().
>
Thanks Bjorn
How about changing to this.
Subject: [PATCH] PCI: declare quirk_huawei_pcie_sva as FIXUP_HEADER
The arm_smmu_probe_device is now called earlier via pci_device_add,
which calls pci_fixup_device(pci_fixup_header, dev),
while originally it is called from pci_bus_add_device,
which calls pci_fixup_device(pci_fixup_final, dev).
So declare the fixup as pci_fixup_header to take effect
before arm_smmu_probe_device.
Calling stack
Before:
[ 1121.314405] arm_smmu_probe_device+0x48/0x450
[ 1121.314410] __iommu_probe_device+0xc4/0x3c8
[ 1121.314412] iommu_probe_device+0x40/0x90
[ 1121.314414] acpi_dma_configure_id+0xb4/0x100
[ 1121.314417] pci_dma_configure+0xf8/0x108
[ 1121.314421] really_probe+0x78/0x278
[ 1121.314425] __driver_probe_device+0x80/0x140
[ 1121.314427] driver_probe_device+0x48/0x130
[ 1121.314430] __device_attach_driver+0xc0/0x108
[ 1121.314432] bus_for_each_drv+0x8c/0xf8
[ 1121.314435] __device_attach+0x104/0x1a0
[ 1121.314437] device_attach+0x1c/0x30
[ 1121.314440] pci_bus_add_device+0xb8/0x1f0
[ 1121.314442] pci_iov_add_virtfn+0x2ac/0x300
Now:
[ 215.072859] arm_smmu_probe_device+0x48/0x450
[ 215.072871] __iommu_probe_device+0xc0/0x468
[ 215.072875] iommu_probe_device+0x40/0x90
[ 215.072877] iommu_bus_notifier+0x38/0x68
[ 215.072879] notifier_call_chain+0x80/0x148
[ 215.072886] blocking_notifier_call_chain+0x50/0x80
[ 215.072889] bus_notify+0x44/0x68
[ 215.072896] device_add+0x580/0x768
[ 215.072898] pci_device_add+0x1e8/0x568
[ 215.072906] pci_iov_add_virtfn+0x198/0x300
Fixes: bcb81ac6ae3c ("iommu: Get DT/ACPI parsing into the proper probe path")
Signed-off-by: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>
Thanks
