On Thu, Oct 10, 2024 at 10:00:21PM +0800, Baolu Lu wrote: > On 2024/10/10 21:25, Liang, Kan wrote: > > On 2024-10-10 6:10 a.m., Jinpu Wang wrote: > > > Hi Greg, > > > > > > > > > On Thu, Oct 10, 2024 at 11:31 AM Greg KH<gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Thu, Oct 10, 2024 at 11:13:42AM +0200, Jinpu Wang wrote: > > > > > Hi Greg, > > > > > > > > > > On Thu, Oct 10, 2024 at 11:07 AM Greg KH<gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > > On Thu, Oct 10, 2024 at 09:31:37AM +0200, Jinpu Wang wrote: > > > > > > > Hello all, > > > > > > > > > > > > > > We are experiencing a boot hang issue when booting kernel version > > > > > > > 6.1.83+ on a Dell Inc. PowerEdge R770 equipped with an Intel Xeon > > > > > > > 6710E processor. After extensive testing and use of `git bisect`, we > > > > > > > have traced the issue to commit: > > > > > > > > > > > > > > `586e19c88a0c ("iommu/vt-d: Retrieve IOMMU perfmon capability information")` > > > > > > > > > > > > > > This commit appears to be part of a larger patchset, which can be found here: > > > > > > > [Patchset on > > > > > > > lore.kernel.org](https://lore.kernel.org/ > > > > > > > lkml/7c4b3e4e-1c5d-04f1-1891-84f686c94736@xxxxxxxxxxxxxxx/T/) > > > > > > > > > > > > > > We attempted to boot with the `intel_iommu=off` option, but the system > > > > > > > hangs in the same manner. However, the system boots successfully after > > > > > > > disabling `CONFIG_INTEL_IOMMU_PERF_EVENTS`. > > > > > > Is there any error messages? Does the latest 6.6.y tree work properly? > > > > > > If so, why not just use that, no new hardware should be using older > > > > > > kernel trees anyway 🙂 > > > > > No error, just hang, I've removed "quiet" and added "debug". > > > > > Yes, the latest 6.6.y tree works for this, but there are other > > > > > problems/dependency we have to solve. > > > > Ok, that implies that we need to add some other patch to 6.1.y, OR we > > > > can revert it from 6.1.y. Let me know what you think is the better > > > > thing to do. > > > > > > > I think better to revert both: > > > 8c91a4bfc7f8 ("iommu: Fix compilation without CONFIG_IOMMU_INTEL") > > I'm not sure about this one. May need baolu's comments. > > I can't find this commit in the mainline kernel. I guess it fixes a > compilation issue in the stable tree? If so, it depends on whether the > issue is still there. It is commit 70bad345e622 ("iommu: Fix compilation without CONFIG_IOMMU_INTEL") in Linus's tree. thanks, greg k-h