[i915 CNL-Y] system hangs soon after bootup
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux-oem (Ubuntu) |
Fix Released
|
Undecided
|
Unassigned | ||
Bionic |
Fix Released
|
Undecided
|
Timo Aaltonen |
Bug Description
CNL-Y SDP machine hangs soon after logging in, and needs this from intel-gfx list:
Author: Chris Wilson <email address hidden>
Date: Tue May 8 13:15:00 2018 +0300
drm/
We assume that the CSB is written using the normal ringbuffer
coherency protocols, as outlined in kernel/
* (HW) (DRIVER)
*
* if (LOAD ->data_tail) { LOAD ->data_head
* (A) smp_rmb() (C)
* STORE $data LOAD $data
* smp_wmb() (B) smp_mb() (D)
* STORE ->data_head STORE ->data_tail
* }
So we assume that the HW fulfils it's ordering requirements, and so we
should use a complimentary rmb() to ensure that our read of its WRITE
pointer is completed before we start accessing the data.
The final mb() is implied by the uncached mmio we perform to inform the
HW of our READ pointer.
References: https:/
References: https:/
References: https:/
References: 61bf9719fa17 ("drm/i915/cnl: Use mmio access to context status buffer")
Suggested-by: Mika Kuoppala <email address hidden>
Signed-off-by: Chris Wilson <email address hidden>
Cc: Mika Kuoppala <email address hidden>
Cc: Joonas Lahtinen <email address hidden>
Cc: Tvrtko Ursulin <email address hidden>
Cc: Michał Winiarski <email address hidden>
Cc: Rafael Antognolli <email address hidden>
Cc: Michel Thierry <email address hidden>
Cc: Timo Aaltonen <email address hidden>
Signed-off-by: Timo Aaltonen <email address hidden>
CVE References
Changed in linux-oem (Ubuntu): | |
status: | New → Invalid |
Changed in linux-oem (Ubuntu Bionic): | |
assignee: | nobody → Timo Aaltonen (tjaalton) |
status: | New → In Progress |
description: | updated |
Changed in linux-oem (Ubuntu Bionic): | |
status: | In Progress → Fix Committed |
Changed in linux-oem (Ubuntu): | |
status: | Invalid → Fix Released |
tags: |
added: kernel-fixup-verification-needed-bionic removed: verification-needed-bionic |
This bug is awaiting verification that the 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- bionic' to 'verification- done-bionic' . If the problem still exists, change the tag 'verification- needed- bionic' to 'verification- failed- bionic' .
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!