Subject: [RFC v2 00/10] pseries/papr-hvpipe: Fix deadlock, races and misc cleanups

From: "Ritesh Harjani (IBM)" <[email-masked]>
Date: Wed, 8 Apr 2026 17:31:30 +0530

While going over papr-hvpipe code, there were a few races & a possible
recursive deadlock identified. This patch series is an attempt to fix those
along with some misc cleanups.  The changes are looking sane to me in v2, so I
would appreciate any reviews, however it still hasn't been tested on the real
HW, which I will test and update.

v1->v2:
========
1. Fix a possible deadlock due to use of spin_lock instead of spin_lock_irqsave.
2. Prevent kernel stack uninit memory leak to userspace
3. Fix the race condition in null-ptr-deref case where there may be an
   msg pending to be consumed from the hvpipe.
4. Fixed error handling in init routine in patch-10

[v1]: https://lore.kernel.org/linuxppc-dev/[email-masked]/#t

Ritesh Harjani (IBM) (10):
  pseries/papr-hvpipe: Fix race with interrupt handler
  pseries/papr-hvpipe: Prevent kernel stack memory leak to userspace
  pseries/papr-hvpipe: Fix null ptr deref in papr_hvpipe_dev_create_handle()
  pseries/papr-hvpipe: Fix the usage of copy_to_user()
  pseries/papr-hvpipe: Simplify spin unlock usage in papr_hvpipe_handle_release()
  pseries/papr-hvpipe: Kill task_struct pointer from struct hvpipe_source_info
  pseries/papr-hvpipe: Refactor and simplify hvpipe_rtas_recv_msg()
  pseries/papr-hvpipe: Simplify error handling in papr_hvpipe_init()
  pseries/papr-hvpipe: Fix style and checkpatch issues in enable_hvpipe_IRQ()
  pseries/papr-hvpipe: Fix error handling in case of init routine fails

 arch/powerpc/platforms/pseries/papr-hvpipe.c | 181 ++++++++++---------
 arch/powerpc/platforms/pseries/papr-hvpipe.h |   1 -
 2 files changed, 97 insertions(+), 85 deletions(-)

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2.39.5