parisc build failures in mainline kernel

From: Guenter Roeck
Date: Wed Nov 03 2021 - 23:16:00 EST


Hi,

the mainline kernel fails to build almost all 'parisc' images.

The first build error is

In file included from <command-line>:
include/linux/sched.h: In function 'task_cpu':
include/linux/sched.h:2129:45: error: 'const struct thread_info' has no member named 'cpu'
2129 | return READ_ONCE(task_thread_info(p)->cpu);
| ^~

with many follow-up errors.

bisect points to commit (merge) 01463374c50e ("Merge tag
'cpu-to-thread_info-v5.16-rc1' of
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux" as the culprit,
and reverting that merge does indeed fix the problem.

Guenter

---
bisect log:

# bad: [79ef0c00142519bc34e1341447f3797436cc48bf] Merge tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
# good: [8bb7eca972ad531c9b149c0a51ab43a417385813] Linux 5.15
git bisect start '79ef0c001425' '8bb7eca972ad'
# good: [8cb1ae19bfae92def42c985417cd6e894ddaa047] Merge tag 'x86-fpu-2021-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
git bisect good 8cb1ae19bfae92def42c985417cd6e894ddaa047
# bad: [73d21a3579818aa0e39de207474a39ca35c7d8cb] Merge tag 'media/v5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
git bisect bad 73d21a3579818aa0e39de207474a39ca35c7d8cb
# good: [c2c88a07d679839ddf236db55b258aaedff819ad] media: Add ADV7610 support for adv7604 driver.
git bisect good c2c88a07d679839ddf236db55b258aaedff819ad
# good: [46f876322820c189ab525cfcba2519a17dbc0a6f] Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
git bisect good 46f876322820c189ab525cfcba2519a17dbc0a6f
# bad: [2dc26d98cfdf756e390013fafaba959b052b0867] Merge tag 'overflow-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
git bisect bad 2dc26d98cfdf756e390013fafaba959b052b0867
# good: [03feb7c55c470158ece9afb317c395cd65bd14ac] Merge tag 'm68k-for-v5.16-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k
git bisect good 03feb7c55c470158ece9afb317c395cd65bd14ac
# good: [caf283d040f53bc4fd81ce3d2a1a364b069cfd7d] xfrm: Use memset_after() to clear padding
git bisect good caf283d040f53bc4fd81ce3d2a1a364b069cfd7d
# bad: [01463374c50e4fe75abec927fa231f8f5d701852] Merge tag 'cpu-to-thread_info-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
git bisect bad 01463374c50e4fe75abec927fa231f8f5d701852
# good: [227d735d889e0403f1659df6e2dece7633f380bc] powerpc: add CPU field to struct thread_info
git bisect good 227d735d889e0403f1659df6e2dece7633f380bc
# good: [336868afbaae2d153fc20268a21747c31e5071b8] powerpc: smp: remove hack to obtain offset of task_struct::cpu
git bisect good 336868afbaae2d153fc20268a21747c31e5071b8
# good: [d9f2a53f64a6fcae994457e64a7124d2a3efd323] Merge tag 'pr-move-task-cpu-to-ti' of git://git.kernel.org/pub/scm/linux/kernel/git/ardb/linux.git
git bisect good d9f2a53f64a6fcae994457e64a7124d2a3efd323
# first bad commit: [01463374c50e4fe75abec927fa231f8f5d701852] Merge tag 'cpu-to-thread_info-v5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux