On Sun, 24 Aug 2025 22:34:14 -0500, Jeremy Linton wrote:

Currently uprobes and the Arm Guarded Control Stack (GCS) feature are
exclusive of each other. This restriction needs to be lifted in order
to utilize GCS for generic Linux distro images where the expectation
is that core debugging features like uprobes work.

This series adds some user accessors to read/push/pop the userspace
shadow stack. It then utilizes those functions in the uprobe paths as
needed to synchronize GCS with the changes in control flow at probe
locations.

[...]

Applied to arm64 (for-next/uprobes), thanks!

[1/7] arm64: probes: Break ret out from bl/blr
      https://git.kernel.org/arm64/c/47687aa4d9c9
[2/7] arm64: uaccess: Move existing GCS accessors definitions to gcs.h
      https://git.kernel.org/arm64/c/ea920b50ac9f
[3/7] arm64: uaccess: Add additional userspace GCS accessors
      https://git.kernel.org/arm64/c/9cd2a7f1180f
[4/7] arm64: probes: Add GCS support to bl/blr/ret
      https://git.kernel.org/arm64/c/efb07ac534e2
[5/7] arm64: uprobes: Add GCS support to uretprobes
      https://git.kernel.org/arm64/c/4a601714bb24
[6/7] arm64: Kconfig: Remove GCS restrictions on UPROBES
      https://git.kernel.org/arm64/c/cc66c711e58f
[7/7] uprobes: uprobe_warn should use passed task
      https://git.kernel.org/arm64/c/ba1afc94deb8

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev