Hello Erv,

Just wanted you to know what I did and found out.

I tried the update grub command when I was in Linux mint OS, it did not have any effect.
Then I remembered reading somebody else has the same issue, no effect until they went into something else on their computer, it had 3-4 letters, I didn't understand, they said the update worked from there because they had loader that software before their Mint software.
So since I used to use UBUNTU, and still have it on my computer, before I loaded Mint, I figured I'd open my UBUNTU software and run the update grub command, then went back into Mint and it worked, I am now running 116 Kernel update.  Good news, but my computer still shows that it cannot find that "boot" file, not sure but then I load the "next volume" and then I can choose to run either Windows, Ubuntu or Mint, so I'm good.

Thanks for your attempt to help Erv.

Ralph Goe




Sent with Proton Mail secure email.

On Thursday, July 18th, 2024 at 9:58 PM, Erv Bendiks <email address hidden> wrote:

> @RogerRamjet> Do you have motherboard,CPU and OS information to share?
> 
> 
> 
> On Thu, Jul 18, 2024 at 6:45 PM Roger Ramjet <email address hidden>
> 
> wrote:
> 
> > Why does the updated kernel show installed but not active, I'm still
> > having a problem?
> > 
> > Sent with Proton Mail secure email.
> > 
> > On Thursday, July 18th, 2024 at 2:47 PM, Pete Orlando
> > <email address hidden> wrote:
> > 
> > > Ok Black screen now fixed after "update Manger" sent new update on
> > > 7/17/2024. Thank You Linux team !
> > > 
> > > On Thu, Jul 18, 2024 at 3:15 AM Roger Ramjet <email address hidden>
> > > 
> > > wrote:
> > > 
> > > > Unfortunately, I still have the same problem, after updating, I power
> > > > down
> > > > and restart, I get:
> > > > error: file `/boot/' not found.
> > > > 
> > > > I view the Kernels in the update manager, it shows 5.15.0-116 is
> > > > "installed" and "supported until April 2027"
> > > > 
> > > > The Kernel is loaded and installed but "not found"
> > > > Then another window opens and I must choose "Boot from next volume"
> > > > Then another window where I'm given the choice of booting from
> > > > 5.15.0-107-generic (on /dev/sda5)
> > > > This new Kernel is not listed at this window, not sure why not, seems
> > > > it
> > > > should be.
> > > > 
> > > > If I can give you more info. let me know.
> > > > 
> > > > Ralph Goe
> > > > 
> > > > Sent with Proton Mail secure email.
> > > > 
> > > > On Monday, July 15th, 2024 at 11:38 PM, Ubuntu Kernel Bot
> > > > <email address hidden> wrote:
> > > > 
> > > > > This bug is awaiting verification that the linux-azure/5.15.0-1069.78
> > > > > kernel in -proposed solves the problem. Please test the kernel and
> > > > > update this bug with the results. If the problem is solved, change
> > > > > the
> > > > > tag 'verification-needed-jammy-linux-azure' to
> > > > > 'verification-done-jammy-
> > > > > linux-azure'. If the problem still exists, change the tag
> > > > > 'verification-
> > > > > needed-jammy-linux-azure' to 'verification-failed-jammy-linux-azure'.
> > > > > 
> > > > > If verification is not done by 5 working days from today, this fix
> > > > > will
> > > > > be dropped from the source code, and this bug will be closed.
> > > > > 
> > > > > See https://wiki.ubuntu.com/Testing/EnableProposed for
> > > > > documentation how
> > > > > to enable and use -proposed. Thank you!
> > > > > 
> > > > > ** Tags added: kernel-spammed-jammy-linux-azure-v2
> > > > > verification-needed-jammy-linux-azure
> > > > > 
> > > > > --
> > > > > You received this bug notification because you are subscribed to a
> > > > > duplicate bug report (2069485).
> > > > > https://bugs.launchpad.net/bugs/2068738
> > > > > 
> > > > > Title:
> > > > > AMD GPUs fail with null pointer dereference when IOMMU enabled,
> > > > > leading to black screen
> > > > > 
> > > > > Status in linux package in Ubuntu:
> > > > > Fix Released
> > > > > Status in linux source package in Jammy:
> > > > > Fix Released
> > > > > 
> > > > > Bug description:
> > > > > BugLink: https://bugs.launchpad.net/bugs/2068738
> > > > > 
> > > > > [Impact]
> > > > > 
> > > > > On systems with AMD Picasso/Raven 2 GPU devices, when the IOMMU is
> > > > > enabled, the system fails to boot correctly, and all users see is a
> > > > > black screen.
> > > > > 
> > > > > This is caused by a null pointer dereference when enabling the IOMMU
> > > > > after the device has been initialised. It should happen the other way
> > > > > around.
> > > > > 
> > > > > AMD-Vi: AMD IOMMUv2 loaded and initialized
> > > > > ...
> > > > > amdgpu: Topology: Add APU node [0x15d8:0x1002]
> > > > > kfd kfd: amdgpu: added device 1002:15d8
> > > > > kfd kfd: amdgpu: Failed to resume IOMMU for device 1002:15d8
> > > > > ...
> > > > > amdgpu 0000:06:00.0: amdgpu: amdgpu_device_ip_init failed
> > > > > amdgpu 0000:06:00.0: amdgpu: Fatal error during GPU init
> > > > > amdgpu 0000:06:00.0: amdgpu: amdgpu: finishing device.
> > > > > ...
> > > > > BUG: kernel NULL pointer dereference, address: 000000000000013c
> > > > > ...
> > > > > CPU: 1 PID: 223 Comm: systemd-udevd Not tainted 5.15.0-112-generic
> > > > > #122-Ubuntu
> > > > > ...
> > > > > RIP: 0010:amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > > > > ...
> > > > > Call Trace:
> > > > > <TASK>
> > > > > 
> > > > > ? srso_return_thunk+0x5/0x10
> > > > > ? show_trace_log_lvl+0x28e/0x2ea
> > > > > ? show_trace_log_lvl+0x28e/0x2ea
> > > > > ? dm_hw_fini+0x23/0x30 [amdgpu]
> > > > > ? show_regs.part.0+0x23/0x29
> > > > > ? __die_body.cold+0x8/0xd
> > > > > ? __die+0x2b/0x37
> > > > > ? page_fault_oops+0x13b/0x170
> > > > > ? srso_return_thunk+0x5/0x10
> > > > > ? do_user_addr_fault+0x321/0x670
> > > > > ? srso_return_thunk+0x5/0x10
> > > > > ? __free_pages_ok+0x34a/0x4f0
> > > > > ? exc_page_fault+0x77/0x170
> > > > > ? asm_exc_page_fault+0x27/0x30
> > > > > ? amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > > > > dm_hw_fini+0x23/0x30 [amdgpu]
> > > > > amdgpu_device_ip_fini_early.isra.0+0x278/0x312 [amdgpu]
> > > > > amdgpu_device_fini_hw+0x156/0x208 [amdgpu]
> > > > > amdgpu_driver_unload_kms+0x69/0x90 [amdgpu]
> > > > > amdgpu_driver_load_kms.cold+0x81/0x107 [amdgpu]
> > > > > amdgpu_pci_probe+0x1d1/0x290 [amdgpu]
> > > > > local_pci_probe+0x4b/0x90
> > > > > ? srso_return_thunk+0x5/0x10
> > > > > pci_device_probe+0x119/0x200
> > > > > really_probe+0x222/0x420
> > > > > __driver_probe_device+0xe8/0x140
> > > > > driver_probe_device+0x23/0xc0
> > > > > __driver_attach+0xf7/0x1f0
> > > > > ? __device_attach_driver+0x140/0x140
> > > > > bus_for_each_dev+0x7f/0xd0
> > > > > driver_attach+0x1e/0x30
> > > > > bus_add_driver+0x148/0x220
> > > > > ? srso_return_thunk+0x5/0x10
> > > > > driver_register+0x95/0x100
> > > > > __pci_register_driver+0x68/0x70
> > > > > amdgpu_init+0x7c/0x1000 [amdgpu]
> > > > > ? 0xffffffffc0e0b000
> > > > > do_one_initcall+0x49/0x1e0
> > > > > ? srso_return_thunk+0x5/0x10
> > > > > ? kmem_cache_alloc_trace+0x19e/0x2e0
> > > > > do_init_module+0x52/0x260
> > > > > load_module+0xb45/0xbe0
> > > > > __do_sys_finit_module+0xbf/0x120
> > > > > __x64_sys_finit_module+0x18/0x20
> > > > > x64_sys_call+0x1ac3/0x1fa0
> > > > > do_syscall_64+0x56/0xb0
> > > > > ...
> > > > > entry_SYSCALL_64_after_hwframe+0x67/0xd1
> > > > > 
> > > > > A workaround does exist. Users can set "nomodeset" or "amd_iommu=off"
> > > > > to GRUB_CMDLINE_LINUX_DEFAULT, update-grub and reboot.
> > > > > 
> > > > > [Fix]
> > > > > 
> > > > > The regression was caused by the following commit that landed in
> > > > > 5.15.0-112-generic, and 5.15.150 upstream:
> > > > > 
> > > > > commit 3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd ubuntu-jammy
> > > > > Author: Yifan Zhang <email address hidden>
> > > > > 
> > > > > Date: Tue Sep 28 15:42:35 2021 +0800
> > > > > Subject: drm/amdgpu: init iommu after amdkfd device init
> > > > > Link:
> > 
> > https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/jammy/commit/?id=3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd
> > 
> > > > > The fix is to revert this patch, as it was not suppose to be
> > > > > backported to 5.15 stable.
> > > > > 
> > > > > The mailing list discussion with AMD developers is:
> > 
> > https://<email address hidden>/
> > 
> > > > > The fix hasn't been acknowledged by Greg KH or Sasha Levin yet, so
> > > > > sending as a Ubuntu SAUCE patch. If the upstream status changes, we
> > > > > can NAK and resend.
> > > > > 
> > > > > [Testcase]
> > > > > 
> > > > > You need a system with an AMD Picasso/Raven 2 device. It will likely
> > > > > be an APU, and not a discrete graphics card, but any AMD
> > > > > Picasso/Raven
> > > > > 2 device is affected.
> > > > > 
> > > > > Install the kernel and boot. Make sure full modesetting is enabled.
> > > > > 
> > > > > There is a test kernel available in the ppa below:
> > > > > 
> > > > > https://launchpad.net/~mruffell/+archive/ubuntu/lp2068738-test
> > > > > 
> > > > > If you install the test kernel, your system should boot successfully.
> > > > > 
> > > > > [Where problems could occur]
> > > > > 
> > > > > We are reverting a problematic patch and going back to how it was
> > > > > before 5.15.0-112-generic. This should not cause any issues for
> > > > > users.
> > > > > 
> > > > > If a regression were to occur, users can set "nomodeset" or
> > > > > "amd_iommu=off" to GRUB_CMDLINE_LINUX_DEFAULT and reboot, or pin
> > > > > their
> > > > > kernel to a working one.
> > > > > 
> > > > > The impact of a regression would be high, as users displays could be
> > > > > blank.
> > > > > 
> > > > > [Other Info]
> > > > > 
> > > > > User reports:
> > > > > https://forums.linuxmint.com/viewtopic.php?t=421484
> > > > > https://forums.linuxmint.com/viewtopic.php?t=421441
> > 
> > https://www.reddit.com/r/Ubuntu/comments/1d9uviz/had_to_purge_kernel_5150112_could_not_boot/
> > 
> > https://www.reddit.com/r/linuxmint/comments/1d9w6c9/kernel_5150112_boot_failure/
> > 
> > > > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068735
> > > > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068793
> > > > > https://bugs.launchpad.net/bugs/2068812
> > > > > 
> > > > > As bizarre as it is, this commit was actually originally included in
> > > > > 5.15-rc5:
> > > > > 
> > > > > commit 714d9e4574d54596973ee3b0624ee4a16264d700
> > > > > Author: Yifan Zhang <email address hidden>
> > > > > 
> > > > > Date: Tue Sep 28 15:42:35 2021 +0800
> > > > > Subject: drm/amdgpu: init iommu after amdkfd device init
> > > > > Link:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=714d9e4574d54596973ee3b0624ee4a16264d700
> > 
> > > > > It seems to have caused issues back then too, and was removed in the
> > > > > following fixups, in 5.16-rc1:
> > > > > 
> > > > > commit 93cec184788b0cf3926bc1f7b47fed74ba87990c
> > > > > Author: James Zhu <email address hidden>
> > > > > 
> > > > > Date: Tue Nov 2 21:33:50 2021 -0400
> > > > > Subject: drm/amdgpu: remove duplicated kfd_resume_iommu
> > > > > Link:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=93cec184788b0cf3926bc1f7b47fed74ba87990c
> > 
> > > > > commit 9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > > > > Author: shaoyunl <email address hidden>
> > > > > 
> > > > > Date: Fri Nov 5 12:34:14 2021 -0400
> > > > > Subject: drm/amd/amdgpu: fix the kfd pre_reset sequence in sriov
> > > > > Link:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > 
> > > > > I'm not exactly in favor of rewriting history twice, so I think we
> > > > > should just revert the upstream stable patch and move on.
> > > > > 
> > > > > To manage notifications about this bug go to:
> > 
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068738/+subscriptions
> > 
> > > > --
> > > > You received this bug notification because you are subscribed to the
> > > > bug
> > > > report.
> > > > https://bugs.launchpad.net/bugs/2068738
> > > > 
> > > > Title:
> > > > AMD GPUs fail with null pointer dereference when IOMMU enabled,
> > > > leading to black screen
> > > > 
> > > > Status in linux package in Ubuntu:
> > > > Fix Released
> > > > Status in linux source package in Jammy:
> > > > Fix Released
> > > > 
> > > > Bug description:
> > > > BugLink: https://bugs.launchpad.net/bugs/2068738
> > > > 
> > > > [Impact]
> > > > 
> > > > On systems with AMD Picasso/Raven 2 GPU devices, when the IOMMU is
> > > > enabled, the system fails to boot correctly, and all users see is a
> > > > black screen.
> > > > 
> > > > This is caused by a null pointer dereference when enabling the IOMMU
> > > > after the device has been initialised. It should happen the other way
> > > > around.
> > > > 
> > > > AMD-Vi: AMD IOMMUv2 loaded and initialized
> > > > ...
> > > > amdgpu: Topology: Add APU node [0x15d8:0x1002]
> > > > kfd kfd: amdgpu: added device 1002:15d8
> > > > kfd kfd: amdgpu: Failed to resume IOMMU for device 1002:15d8
> > > > ...
> > > > amdgpu 0000:06:00.0: amdgpu: amdgpu_device_ip_init failed
> > > > amdgpu 0000:06:00.0: amdgpu: Fatal error during GPU init
> > > > amdgpu 0000:06:00.0: amdgpu: amdgpu: finishing device.
> > > > ...
> > > > BUG: kernel NULL pointer dereference, address: 000000000000013c
> > > > ...
> > > > CPU: 1 PID: 223 Comm: systemd-udevd Not tainted 5.15.0-112-generic
> > > > #122-Ubuntu
> > > > ...
> > > > RIP: 0010:amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > > > ...
> > > > Call Trace:
> > > > <TASK>
> > > > ? srso_return_thunk+0x5/0x10
> > > > ? show_trace_log_lvl+0x28e/0x2ea
> > > > ? show_trace_log_lvl+0x28e/0x2ea
> > > > ? dm_hw_fini+0x23/0x30 [amdgpu]
> > > > ? show_regs.part.0+0x23/0x29
> > > > ? __die_body.cold+0x8/0xd
> > > > ? __die+0x2b/0x37
> > > > ? page_fault_oops+0x13b/0x170
> > > > ? srso_return_thunk+0x5/0x10
> > > > ? do_user_addr_fault+0x321/0x670
> > > > ? srso_return_thunk+0x5/0x10
> > > > ? __free_pages_ok+0x34a/0x4f0
> > > > ? exc_page_fault+0x77/0x170
> > > > ? asm_exc_page_fault+0x27/0x30
> > > > ? amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > > > dm_hw_fini+0x23/0x30 [amdgpu]
> > > > amdgpu_device_ip_fini_early.isra.0+0x278/0x312 [amdgpu]
> > > > amdgpu_device_fini_hw+0x156/0x208 [amdgpu]
> > > > amdgpu_driver_unload_kms+0x69/0x90 [amdgpu]
> > > > amdgpu_driver_load_kms.cold+0x81/0x107 [amdgpu]
> > > > amdgpu_pci_probe+0x1d1/0x290 [amdgpu]
> > > > local_pci_probe+0x4b/0x90
> > > > ? srso_return_thunk+0x5/0x10
> > > > pci_device_probe+0x119/0x200
> > > > really_probe+0x222/0x420
> > > > __driver_probe_device+0xe8/0x140
> > > > driver_probe_device+0x23/0xc0
> > > > __driver_attach+0xf7/0x1f0
> > > > ? __device_attach_driver+0x140/0x140
> > > > bus_for_each_dev+0x7f/0xd0
> > > > driver_attach+0x1e/0x30
> > > > bus_add_driver+0x148/0x220
> > > > ? srso_return_thunk+0x5/0x10
> > > > driver_register+0x95/0x100
> > > > __pci_register_driver+0x68/0x70
> > > > amdgpu_init+0x7c/0x1000 [amdgpu]
> > > > ? 0xffffffffc0e0b000
> > > > do_one_initcall+0x49/0x1e0
> > > > ? srso_return_thunk+0x5/0x10
> > > > ? kmem_cache_alloc_trace+0x19e/0x2e0
> > > > do_init_module+0x52/0x260
> > > > load_module+0xb45/0xbe0
> > > > __do_sys_finit_module+0xbf/0x120
> > > > __x64_sys_finit_module+0x18/0x20
> > > > x64_sys_call+0x1ac3/0x1fa0
> > > > do_syscall_64+0x56/0xb0
> > > > ...
> > > > entry_SYSCALL_64_after_hwframe+0x67/0xd1
> > > > 
> > > > A workaround does exist. Users can set "nomodeset" or "amd_iommu=off"
> > > > to GRUB_CMDLINE_LINUX_DEFAULT, update-grub and reboot.
> > > > 
> > > > [Fix]
> > > > 
> > > > The regression was caused by the following commit that landed in
> > > > 5.15.0-112-generic, and 5.15.150 upstream:
> > > > 
> > > > commit 3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd ubuntu-jammy
> > > > Author: Yifan Zhang <email address hidden>
> > > > Date: Tue Sep 28 15:42:35 2021 +0800
> > > > Subject: drm/amdgpu: init iommu after amdkfd device init
> > > > Link:
> > 
> > https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/jammy/commit/?id=3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd
> > 
> > > > The fix is to revert this patch, as it was not suppose to be
> > > > backported to 5.15 stable.
> > > > 
> > > > The mailing list discussion with AMD developers is:
> > > > 
> > > > https://<email address hidden>/
> > > > 
> > > > The fix hasn't been acknowledged by Greg KH or Sasha Levin yet, so
> > > > sending as a Ubuntu SAUCE patch. If the upstream status changes, we
> > > > can NAK and resend.
> > > > 
> > > > [Testcase]
> > > > 
> > > > You need a system with an AMD Picasso/Raven 2 device. It will likely
> > > > be an APU, and not a discrete graphics card, but any AMD Picasso/Raven
> > > > 2 device is affected.
> > > > 
> > > > Install the kernel and boot. Make sure full modesetting is enabled.
> > > > 
> > > > There is a test kernel available in the ppa below:
> > > > 
> > > > https://launchpad.net/~mruffell/+archive/ubuntu/lp2068738-test
> > > > 
> > > > If you install the test kernel, your system should boot successfully.
> > > > 
> > > > [Where problems could occur]
> > > > 
> > > > We are reverting a problematic patch and going back to how it was
> > > > before 5.15.0-112-generic. This should not cause any issues for users.
> > > > 
> > > > If a regression were to occur, users can set "nomodeset" or
> > > > "amd_iommu=off" to GRUB_CMDLINE_LINUX_DEFAULT and reboot, or pin their
> > > > kernel to a working one.
> > > > 
> > > > The impact of a regression would be high, as users displays could be
> > > > blank.
> > > > 
> > > > [Other Info]
> > > > 
> > > > User reports:
> > > > https://forums.linuxmint.com/viewtopic.php?t=421484
> > > > https://forums.linuxmint.com/viewtopic.php?t=421441
> > 
> > https://www.reddit.com/r/Ubuntu/comments/1d9uviz/had_to_purge_kernel_5150112_could_not_boot/
> > 
> > https://www.reddit.com/r/linuxmint/comments/1d9w6c9/kernel_5150112_boot_failure/
> > 
> > > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068735
> > > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068793
> > > > https://bugs.launchpad.net/bugs/2068812
> > > > 
> > > > As bizarre as it is, this commit was actually originally included in
> > > > 5.15-rc5:
> > > > 
> > > > commit 714d9e4574d54596973ee3b0624ee4a16264d700
> > > > Author: Yifan Zhang <email address hidden>
> > > > Date: Tue Sep 28 15:42:35 2021 +0800
> > > > Subject: drm/amdgpu: init iommu after amdkfd device init
> > > > Link:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=714d9e4574d54596973ee3b0624ee4a16264d700
> > 
> > > > It seems to have caused issues back then too, and was removed in the
> > > > following fixups, in 5.16-rc1:
> > > > 
> > > > commit 93cec184788b0cf3926bc1f7b47fed74ba87990c
> > > > Author: James Zhu <email address hidden>
> > > > Date: Tue Nov 2 21:33:50 2021 -0400
> > > > Subject: drm/amdgpu: remove duplicated kfd_resume_iommu
> > > > Link:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=93cec184788b0cf3926bc1f7b47fed74ba87990c
> > 
> > > > commit 9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > > > Author: shaoyunl <email address hidden>
> > > > Date: Fri Nov 5 12:34:14 2021 -0400
> > > > Subject: drm/amd/amdgpu: fix the kfd pre_reset sequence in sriov
> > > > Link:
> > 
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > 
> > > > I'm not exactly in favor of rewriting history twice, so I think we
> > > > should just revert the upstream stable patch and move on.
> > > > 
> > > > To manage notifications about this bug go to:
> > 
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068738/+subscriptions
> > 
> > > --
> > > You received this bug notification because you are subscribed to a
> > > duplicate bug report (2069485).
> > > https://bugs.launchpad.net/bugs/2068738
> > > 
> > > Title:
> > > AMD GPUs fail with null pointer dereference when IOMMU enabled,
> > > leading to black screen
> > > 
> > > Status in linux package in Ubuntu:
> > > Fix Released
> > > Status in linux source package in Jammy:
> > > Fix Released
> > > 
> > > Bug description:
> > > BugLink: https://bugs.launchpad.net/bugs/2068738
> > > 
> > > [Impact]
> > > 
> > > On systems with AMD Picasso/Raven 2 GPU devices, when the IOMMU is
> > > enabled, the system fails to boot correctly, and all users see is a
> > > black screen.
> > > 
> > > This is caused by a null pointer dereference when enabling the IOMMU
> > > after the device has been initialised. It should happen the other way
> > > around.
> > > 
> > > AMD-Vi: AMD IOMMUv2 loaded and initialized
> > > ...
> > > amdgpu: Topology: Add APU node [0x15d8:0x1002]
> > > kfd kfd: amdgpu: added device 1002:15d8
> > > kfd kfd: amdgpu: Failed to resume IOMMU for device 1002:15d8
> > > ...
> > > amdgpu 0000:06:00.0: amdgpu: amdgpu_device_ip_init failed
> > > amdgpu 0000:06:00.0: amdgpu: Fatal error during GPU init
> > > amdgpu 0000:06:00.0: amdgpu: amdgpu: finishing device.
> > > ...
> > > BUG: kernel NULL pointer dereference, address: 000000000000013c
> > > ...
> > > CPU: 1 PID: 223 Comm: systemd-udevd Not tainted 5.15.0-112-generic
> > > #122-Ubuntu
> > > ...
> > > RIP: 0010:amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > > ...
> > > Call Trace:
> > > <TASK>
> > > 
> > > ? srso_return_thunk+0x5/0x10
> > > ? show_trace_log_lvl+0x28e/0x2ea
> > > ? show_trace_log_lvl+0x28e/0x2ea
> > > ? dm_hw_fini+0x23/0x30 [amdgpu]
> > > ? show_regs.part.0+0x23/0x29
> > > ? __die_body.cold+0x8/0xd
> > > ? __die+0x2b/0x37
> > > ? page_fault_oops+0x13b/0x170
> > > ? srso_return_thunk+0x5/0x10
> > > ? do_user_addr_fault+0x321/0x670
> > > ? srso_return_thunk+0x5/0x10
> > > ? __free_pages_ok+0x34a/0x4f0
> > > ? exc_page_fault+0x77/0x170
> > > ? asm_exc_page_fault+0x27/0x30
> > > ? amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > > dm_hw_fini+0x23/0x30 [amdgpu]
> > > amdgpu_device_ip_fini_early.isra.0+0x278/0x312 [amdgpu]
> > > amdgpu_device_fini_hw+0x156/0x208 [amdgpu]
> > > amdgpu_driver_unload_kms+0x69/0x90 [amdgpu]
> > > amdgpu_driver_load_kms.cold+0x81/0x107 [amdgpu]
> > > amdgpu_pci_probe+0x1d1/0x290 [amdgpu]
> > > local_pci_probe+0x4b/0x90
> > > ? srso_return_thunk+0x5/0x10
> > > pci_device_probe+0x119/0x200
> > > really_probe+0x222/0x420
> > > __driver_probe_device+0xe8/0x140
> > > driver_probe_device+0x23/0xc0
> > > __driver_attach+0xf7/0x1f0
> > > ? __device_attach_driver+0x140/0x140
> > > bus_for_each_dev+0x7f/0xd0
> > > driver_attach+0x1e/0x30
> > > bus_add_driver+0x148/0x220
> > > ? srso_return_thunk+0x5/0x10
> > > driver_register+0x95/0x100
> > > __pci_register_driver+0x68/0x70
> > > amdgpu_init+0x7c/0x1000 [amdgpu]
> > > ? 0xffffffffc0e0b000
> > > do_one_initcall+0x49/0x1e0
> > > ? srso_return_thunk+0x5/0x10
> > > ? kmem_cache_alloc_trace+0x19e/0x2e0
> > > do_init_module+0x52/0x260
> > > load_module+0xb45/0xbe0
> > > __do_sys_finit_module+0xbf/0x120
> > > __x64_sys_finit_module+0x18/0x20
> > > x64_sys_call+0x1ac3/0x1fa0
> > > do_syscall_64+0x56/0xb0
> > > ...
> > > entry_SYSCALL_64_after_hwframe+0x67/0xd1
> > > 
> > > A workaround does exist. Users can set "nomodeset" or "amd_iommu=off"
> > > to GRUB_CMDLINE_LINUX_DEFAULT, update-grub and reboot.
> > > 
> > > [Fix]
> > > 
> > > The regression was caused by the following commit that landed in
> > > 5.15.0-112-generic, and 5.15.150 upstream:
> > > 
> > > commit 3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd ubuntu-jammy
> > > Author: Yifan Zhang <email address hidden>
> > > 
> > > Date: Tue Sep 28 15:42:35 2021 +0800
> > > Subject: drm/amdgpu: init iommu after amdkfd device init
> > > Link:
> > > https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/jammy/commit/?id=3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd
> > > 
> > > The fix is to revert this patch, as it was not suppose to be
> > > backported to 5.15 stable.
> > > 
> > > The mailing list discussion with AMD developers is:
> > > 
> > > https://<email address hidden>/
> > > 
> > > The fix hasn't been acknowledged by Greg KH or Sasha Levin yet, so
> > > sending as a Ubuntu SAUCE patch. If the upstream status changes, we
> > > can NAK and resend.
> > > 
> > > [Testcase]
> > > 
> > > You need a system with an AMD Picasso/Raven 2 device. It will likely
> > > be an APU, and not a discrete graphics card, but any AMD Picasso/Raven
> > > 2 device is affected.
> > > 
> > > Install the kernel and boot. Make sure full modesetting is enabled.
> > > 
> > > There is a test kernel available in the ppa below:
> > > 
> > > https://launchpad.net/~mruffell/+archive/ubuntu/lp2068738-test
> > > 
> > > If you install the test kernel, your system should boot successfully.
> > > 
> > > [Where problems could occur]
> > > 
> > > We are reverting a problematic patch and going back to how it was
> > > before 5.15.0-112-generic. This should not cause any issues for users.
> > > 
> > > If a regression were to occur, users can set "nomodeset" or
> > > "amd_iommu=off" to GRUB_CMDLINE_LINUX_DEFAULT and reboot, or pin their
> > > kernel to a working one.
> > > 
> > > The impact of a regression would be high, as users displays could be
> > > blank.
> > > 
> > > [Other Info]
> > > 
> > > User reports:
> > > https://forums.linuxmint.com/viewtopic.php?t=421484
> > > https://forums.linuxmint.com/viewtopic.php?t=421441
> > 
> > https://www.reddit.com/r/Ubuntu/comments/1d9uviz/had_to_purge_kernel_5150112_could_not_boot/
> > 
> > https://www.reddit.com/r/linuxmint/comments/1d9w6c9/kernel_5150112_boot_failure/
> > 
> > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068735
> > > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068793
> > > https://bugs.launchpad.net/bugs/2068812
> > > 
> > > As bizarre as it is, this commit was actually originally included in
> > > 5.15-rc5:
> > > 
> > > commit 714d9e4574d54596973ee3b0624ee4a16264d700
> > > Author: Yifan Zhang <email address hidden>
> > > 
> > > Date: Tue Sep 28 15:42:35 2021 +0800
> > > Subject: drm/amdgpu: init iommu after amdkfd device init
> > > Link:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=714d9e4574d54596973ee3b0624ee4a16264d700
> > > 
> > > It seems to have caused issues back then too, and was removed in the
> > > following fixups, in 5.16-rc1:
> > > 
> > > commit 93cec184788b0cf3926bc1f7b47fed74ba87990c
> > > Author: James Zhu <email address hidden>
> > > 
> > > Date: Tue Nov 2 21:33:50 2021 -0400
> > > Subject: drm/amdgpu: remove duplicated kfd_resume_iommu
> > > Link:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=93cec184788b0cf3926bc1f7b47fed74ba87990c
> > > 
> > > commit 9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > > Author: shaoyunl <email address hidden>
> > > 
> > > Date: Fri Nov 5 12:34:14 2021 -0400
> > > Subject: drm/amd/amdgpu: fix the kfd pre_reset sequence in sriov
> > > Link:
> > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > > 
> > > I'm not exactly in favor of rewriting history twice, so I think we
> > > should just revert the upstream stable patch and move on.
> > > 
> > > To manage notifications about this bug go to:
> > 
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068738/+subscriptions
> > 
> > --
> > You received this bug notification because you are subscribed to the bug
> > report.
> > https://bugs.launchpad.net/bugs/2068738
> > 
> > Title:
> > AMD GPUs fail with null pointer dereference when IOMMU enabled,
> > leading to black screen
> > 
> > Status in linux package in Ubuntu:
> > Fix Released
> > Status in linux source package in Jammy:
> > Fix Released
> > 
> > Bug description:
> > BugLink: https://bugs.launchpad.net/bugs/2068738
> > 
> > [Impact]
> > 
> > On systems with AMD Picasso/Raven 2 GPU devices, when the IOMMU is
> > enabled, the system fails to boot correctly, and all users see is a
> > black screen.
> > 
> > This is caused by a null pointer dereference when enabling the IOMMU
> > after the device has been initialised. It should happen the other way
> > around.
> > 
> > AMD-Vi: AMD IOMMUv2 loaded and initialized
> > ...
> > amdgpu: Topology: Add APU node [0x15d8:0x1002]
> > kfd kfd: amdgpu: added device 1002:15d8
> > kfd kfd: amdgpu: Failed to resume IOMMU for device 1002:15d8
> > ...
> > amdgpu 0000:06:00.0: amdgpu: amdgpu_device_ip_init failed
> > amdgpu 0000:06:00.0: amdgpu: Fatal error during GPU init
> > amdgpu 0000:06:00.0: amdgpu: amdgpu: finishing device.
> > ...
> > BUG: kernel NULL pointer dereference, address: 000000000000013c
> > ...
> > CPU: 1 PID: 223 Comm: systemd-udevd Not tainted 5.15.0-112-generic
> > #122-Ubuntu
> > ...
> > RIP: 0010:amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > ...
> > Call Trace:
> > <TASK>
> > ? srso_return_thunk+0x5/0x10
> > ? show_trace_log_lvl+0x28e/0x2ea
> > ? show_trace_log_lvl+0x28e/0x2ea
> > ? dm_hw_fini+0x23/0x30 [amdgpu]
> > ? show_regs.part.0+0x23/0x29
> > ? __die_body.cold+0x8/0xd
> > ? __die+0x2b/0x37
> > ? page_fault_oops+0x13b/0x170
> > ? srso_return_thunk+0x5/0x10
> > ? do_user_addr_fault+0x321/0x670
> > ? srso_return_thunk+0x5/0x10
> > ? __free_pages_ok+0x34a/0x4f0
> > ? exc_page_fault+0x77/0x170
> > ? asm_exc_page_fault+0x27/0x30
> > ? amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> > dm_hw_fini+0x23/0x30 [amdgpu]
> > amdgpu_device_ip_fini_early.isra.0+0x278/0x312 [amdgpu]
> > amdgpu_device_fini_hw+0x156/0x208 [amdgpu]
> > amdgpu_driver_unload_kms+0x69/0x90 [amdgpu]
> > amdgpu_driver_load_kms.cold+0x81/0x107 [amdgpu]
> > amdgpu_pci_probe+0x1d1/0x290 [amdgpu]
> > local_pci_probe+0x4b/0x90
> > ? srso_return_thunk+0x5/0x10
> > pci_device_probe+0x119/0x200
> > really_probe+0x222/0x420
> > __driver_probe_device+0xe8/0x140
> > driver_probe_device+0x23/0xc0
> > __driver_attach+0xf7/0x1f0
> > ? __device_attach_driver+0x140/0x140
> > bus_for_each_dev+0x7f/0xd0
> > driver_attach+0x1e/0x30
> > bus_add_driver+0x148/0x220
> > ? srso_return_thunk+0x5/0x10
> > driver_register+0x95/0x100
> > __pci_register_driver+0x68/0x70
> > amdgpu_init+0x7c/0x1000 [amdgpu]
> > ? 0xffffffffc0e0b000
> > do_one_initcall+0x49/0x1e0
> > ? srso_return_thunk+0x5/0x10
> > ? kmem_cache_alloc_trace+0x19e/0x2e0
> > do_init_module+0x52/0x260
> > load_module+0xb45/0xbe0
> > __do_sys_finit_module+0xbf/0x120
> > __x64_sys_finit_module+0x18/0x20
> > x64_sys_call+0x1ac3/0x1fa0
> > do_syscall_64+0x56/0xb0
> > ...
> > entry_SYSCALL_64_after_hwframe+0x67/0xd1
> > 
> > A workaround does exist. Users can set "nomodeset" or "amd_iommu=off"
> > to GRUB_CMDLINE_LINUX_DEFAULT, update-grub and reboot.
> > 
> > [Fix]
> > 
> > The regression was caused by the following commit that landed in
> > 5.15.0-112-generic, and 5.15.150 upstream:
> > 
> > commit 3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd ubuntu-jammy
> > Author: Yifan Zhang <email address hidden>
> > Date: Tue Sep 28 15:42:35 2021 +0800
> > Subject: drm/amdgpu: init iommu after amdkfd device init
> > Link:
> > https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/jammy/commit/?id=3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd
> > 
> > The fix is to revert this patch, as it was not suppose to be
> > backported to 5.15 stable.
> > 
> > The mailing list discussion with AMD developers is:
> > 
> > https://<email address hidden>/
> > 
> > The fix hasn't been acknowledged by Greg KH or Sasha Levin yet, so
> > sending as a Ubuntu SAUCE patch. If the upstream status changes, we
> > can NAK and resend.
> > 
> > [Testcase]
> > 
> > You need a system with an AMD Picasso/Raven 2 device. It will likely
> > be an APU, and not a discrete graphics card, but any AMD Picasso/Raven
> > 2 device is affected.
> > 
> > Install the kernel and boot. Make sure full modesetting is enabled.
> > 
> > There is a test kernel available in the ppa below:
> > 
> > https://launchpad.net/~mruffell/+archive/ubuntu/lp2068738-test
> > 
> > If you install the test kernel, your system should boot successfully.
> > 
> > [Where problems could occur]
> > 
> > We are reverting a problematic patch and going back to how it was
> > before 5.15.0-112-generic. This should not cause any issues for users.
> > 
> > If a regression were to occur, users can set "nomodeset" or
> > "amd_iommu=off" to GRUB_CMDLINE_LINUX_DEFAULT and reboot, or pin their
> > kernel to a working one.
> > 
> > The impact of a regression would be high, as users displays could be
> > blank.
> > 
> > [Other Info]
> > 
> > User reports:
> > https://forums.linuxmint.com/viewtopic.php?t=421484
> > https://forums.linuxmint.com/viewtopic.php?t=421441
> > 
> > https://www.reddit.com/r/Ubuntu/comments/1d9uviz/had_to_purge_kernel_5150112_could_not_boot/
> > 
> > https://www.reddit.com/r/linuxmint/comments/1d9w6c9/kernel_5150112_boot_failure/
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068735
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068793
> > https://bugs.launchpad.net/bugs/2068812
> > 
> > As bizarre as it is, this commit was actually originally included in
> > 5.15-rc5:
> > 
> > commit 714d9e4574d54596973ee3b0624ee4a16264d700
> > Author: Yifan Zhang <email address hidden>
> > Date: Tue Sep 28 15:42:35 2021 +0800
> > Subject: drm/amdgpu: init iommu after amdkfd device init
> > Link:
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=714d9e4574d54596973ee3b0624ee4a16264d700
> > 
> > It seems to have caused issues back then too, and was removed in the
> > following fixups, in 5.16-rc1:
> > 
> > commit 93cec184788b0cf3926bc1f7b47fed74ba87990c
> > Author: James Zhu <email address hidden>
> > Date: Tue Nov 2 21:33:50 2021 -0400
> > Subject: drm/amdgpu: remove duplicated kfd_resume_iommu
> > Link:
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=93cec184788b0cf3926bc1f7b47fed74ba87990c
> > 
> > commit 9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > Author: shaoyunl <email address hidden>
> > Date: Fri Nov 5 12:34:14 2021 -0400
> > Subject: drm/amd/amdgpu: fix the kfd pre_reset sequence in sriov
> > Link:
> > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> > 
> > I'm not exactly in favor of rewriting history twice, so I think we
> > should just revert the upstream stable patch and move on.
> > 
> > To manage notifications about this bug go to:
> > https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068738/+subscriptions
> 
> 
> --
> Erv Bendiks
> 
> 416-816-9802
> 
> --
> You received this bug notification because you are subscribed to a
> duplicate bug report (2069485).
> https://bugs.launchpad.net/bugs/2068738
> 
> Title:
> AMD GPUs fail with null pointer dereference when IOMMU enabled,
> leading to black screen
> 
> Status in linux package in Ubuntu:
> Fix Released
> Status in linux source package in Jammy:
> Fix Released
> 
> Bug description:
> BugLink: https://bugs.launchpad.net/bugs/2068738
> 
> [Impact]
> 
> On systems with AMD Picasso/Raven 2 GPU devices, when the IOMMU is
> enabled, the system fails to boot correctly, and all users see is a
> black screen.
> 
> This is caused by a null pointer dereference when enabling the IOMMU
> after the device has been initialised. It should happen the other way
> around.
> 
> AMD-Vi: AMD IOMMUv2 loaded and initialized
> ...
> amdgpu: Topology: Add APU node [0x15d8:0x1002]
> kfd kfd: amdgpu: added device 1002:15d8
> kfd kfd: amdgpu: Failed to resume IOMMU for device 1002:15d8
> ...
> amdgpu 0000:06:00.0: amdgpu: amdgpu_device_ip_init failed
> amdgpu 0000:06:00.0: amdgpu: Fatal error during GPU init
> amdgpu 0000:06:00.0: amdgpu: amdgpu: finishing device.
> ...
> BUG: kernel NULL pointer dereference, address: 000000000000013c
> ...
> CPU: 1 PID: 223 Comm: systemd-udevd Not tainted 5.15.0-112-generic #122-Ubuntu
> ...
> RIP: 0010:amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> ...
> Call Trace:
> <TASK>
> 
> ? srso_return_thunk+0x5/0x10
> ? show_trace_log_lvl+0x28e/0x2ea
> ? show_trace_log_lvl+0x28e/0x2ea
> ? dm_hw_fini+0x23/0x30 [amdgpu]
> ? show_regs.part.0+0x23/0x29
> ? __die_body.cold+0x8/0xd
> ? __die+0x2b/0x37
> ? page_fault_oops+0x13b/0x170
> ? srso_return_thunk+0x5/0x10
> ? do_user_addr_fault+0x321/0x670
> ? srso_return_thunk+0x5/0x10
> ? __free_pages_ok+0x34a/0x4f0
> ? exc_page_fault+0x77/0x170
> ? asm_exc_page_fault+0x27/0x30
> ? amdgpu_dm_fini+0x149/0x1f0 [amdgpu]
> dm_hw_fini+0x23/0x30 [amdgpu]
> amdgpu_device_ip_fini_early.isra.0+0x278/0x312 [amdgpu]
> amdgpu_device_fini_hw+0x156/0x208 [amdgpu]
> amdgpu_driver_unload_kms+0x69/0x90 [amdgpu]
> amdgpu_driver_load_kms.cold+0x81/0x107 [amdgpu]
> amdgpu_pci_probe+0x1d1/0x290 [amdgpu]
> local_pci_probe+0x4b/0x90
> ? srso_return_thunk+0x5/0x10
> pci_device_probe+0x119/0x200
> really_probe+0x222/0x420
> __driver_probe_device+0xe8/0x140
> driver_probe_device+0x23/0xc0
> __driver_attach+0xf7/0x1f0
> ? __device_attach_driver+0x140/0x140
> bus_for_each_dev+0x7f/0xd0
> driver_attach+0x1e/0x30
> bus_add_driver+0x148/0x220
> ? srso_return_thunk+0x5/0x10
> driver_register+0x95/0x100
> __pci_register_driver+0x68/0x70
> amdgpu_init+0x7c/0x1000 [amdgpu]
> ? 0xffffffffc0e0b000
> do_one_initcall+0x49/0x1e0
> ? srso_return_thunk+0x5/0x10
> ? kmem_cache_alloc_trace+0x19e/0x2e0
> do_init_module+0x52/0x260
> load_module+0xb45/0xbe0
> __do_sys_finit_module+0xbf/0x120
> __x64_sys_finit_module+0x18/0x20
> x64_sys_call+0x1ac3/0x1fa0
> do_syscall_64+0x56/0xb0
> ...
> entry_SYSCALL_64_after_hwframe+0x67/0xd1
> 
> A workaround does exist. Users can set "nomodeset" or "amd_iommu=off"
> to GRUB_CMDLINE_LINUX_DEFAULT, update-grub and reboot.
> 
> [Fix]
> 
> The regression was caused by the following commit that landed in
> 5.15.0-112-generic, and 5.15.150 upstream:
> 
> commit 3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd ubuntu-jammy
> Author: Yifan Zhang <email address hidden>
> 
> Date: Tue Sep 28 15:42:35 2021 +0800
> Subject: drm/amdgpu: init iommu after amdkfd device init
> Link: https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/jammy/commit/?id=3c7e53c0d4b43ffe6e7715414b5f2b3177881ecd
> 
> The fix is to revert this patch, as it was not suppose to be
> backported to 5.15 stable.
> 
> The mailing list discussion with AMD developers is:
> 
> https://<email address hidden>/
> 
> The fix hasn't been acknowledged by Greg KH or Sasha Levin yet, so
> sending as a Ubuntu SAUCE patch. If the upstream status changes, we
> can NAK and resend.
> 
> [Testcase]
> 
> You need a system with an AMD Picasso/Raven 2 device. It will likely
> be an APU, and not a discrete graphics card, but any AMD Picasso/Raven
> 2 device is affected.
> 
> Install the kernel and boot. Make sure full modesetting is enabled.
> 
> There is a test kernel available in the ppa below:
> 
> https://launchpad.net/~mruffell/+archive/ubuntu/lp2068738-test
> 
> If you install the test kernel, your system should boot successfully.
> 
> [Where problems could occur]
> 
> We are reverting a problematic patch and going back to how it was
> before 5.15.0-112-generic. This should not cause any issues for users.
> 
> If a regression were to occur, users can set "nomodeset" or
> "amd_iommu=off" to GRUB_CMDLINE_LINUX_DEFAULT and reboot, or pin their
> kernel to a working one.
> 
> The impact of a regression would be high, as users displays could be
> blank.
> 
> [Other Info]
> 
> User reports:
> https://forums.linuxmint.com/viewtopic.php?t=421484
> https://forums.linuxmint.com/viewtopic.php?t=421441
> https://www.reddit.com/r/Ubuntu/comments/1d9uviz/had_to_purge_kernel_5150112_could_not_boot/
> https://www.reddit.com/r/linuxmint/comments/1d9w6c9/kernel_5150112_boot_failure/
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068735
> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2068793
> https://bugs.launchpad.net/bugs/2068812
> 
> As bizarre as it is, this commit was actually originally included in
> 5.15-rc5:
> 
> commit 714d9e4574d54596973ee3b0624ee4a16264d700
> Author: Yifan Zhang <email address hidden>
> 
> Date: Tue Sep 28 15:42:35 2021 +0800
> Subject: drm/amdgpu: init iommu after amdkfd device init
> Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=714d9e4574d54596973ee3b0624ee4a16264d700
> 
> It seems to have caused issues back then too, and was removed in the
> following fixups, in 5.16-rc1:
> 
> commit 93cec184788b0cf3926bc1f7b47fed74ba87990c
> Author: James Zhu <email address hidden>
> 
> Date: Tue Nov 2 21:33:50 2021 -0400
> Subject: drm/amdgpu: remove duplicated kfd_resume_iommu
> Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=93cec184788b0cf3926bc1f7b47fed74ba87990c
> 
> commit 9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> Author: shaoyunl <email address hidden>
> 
> Date: Fri Nov 5 12:34:14 2021 -0400
> Subject: drm/amd/amdgpu: fix the kfd pre_reset sequence in sriov
> Link: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9f4f2c1a35248f56b2a9c1c004e0aaff3609b15d
> 
> I'm not exactly in favor of rewriting history twice, so I think we
> should just revert the upstream stable patch and move on.
> 
> To manage notifications about this bug go to:
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