linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
* [PATCH v6 0/7] arm64: Enable UPROBES with GCS
@ 2025-08-18 21:34 Jeremy Linton
  2025-08-18 21:34 ` [PATCH v6 1/7] arm64: probes: Break ret out from bl/blr Jeremy Linton
                   ` (6 more replies)
  0 siblings, 7 replies; 10+ messages in thread
From: Jeremy Linton @ 2025-08-18 21:34 UTC (permalink / raw)
  To: linux-trace-kernel
  Cc: linux-perf-users, mhiramat, oleg, peterz, mingo, acme, namhyung,
	mark.rutland, alexander.shishkin, jolsa, irogers, adrian.hunter,
	kan.liang, thiago.bauermann, broonie, yury.khrustalev,
	kristina.martsenko, liaochang1, catalin.marinas, will,
	linux-arm-kernel, linux-kernel, Jeremy Linton

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.

The KCONFIG restriction is then dropped.

v5->v6: Add additional review-by's
	Post the version with the complete function rename that
	     builds with/without GCS (patch 3)
	Drank my coffee before posting this time.

v4->v5: Fix ret xn handing
	Renames, comment tweaks, formatting, per review comments
	rebase 6.17, drop first patch
	Add reviewed-by's

v3->v4: Much delayed v4 rebased to 6.16
	Move existing gcs accessors to gcs.h and then add the new
	     ones. This fixes some of the forward reference issues,
	     the build break and keeps them all together.

v2->v3: Cleanup RET logic to alwaays use LR, and not update IP on aborts
	Correct generic uprobe_warn bug even though we aren't using it

v1->v2:
	Drop uprobe_warn() patch
	Fix copy_thread_gcs() bug created by fixing task_gcs_el0_enabled()
	Comments, now describe issues with reading userspace GCS pages
	Rebased to 6.15

Jeremy Linton (7):
  arm64: probes: Break ret out from bl/blr
  arm64: uaccess: Move existing GCS accessors definitions to gcs.h
  arm64: uaccess: Add additional userspace GCS accessors
  arm64: probes: Add GCS support to bl/blr/ret
  arm64: uprobes: Add GCS support to uretprobes
  arm64: Kconfig: Remove GCS restrictions on UPROBES
  uprobes: uprobe_warn should use passed task

 arch/arm64/Kconfig                       |  1 -
 arch/arm64/include/asm/gcs.h             | 89 ++++++++++++++++++++++++
 arch/arm64/include/asm/uaccess.h         | 40 -----------
 arch/arm64/kernel/probes/decode-insn.c   |  7 +-
 arch/arm64/kernel/probes/simulate-insn.c | 50 ++++++++++---
 arch/arm64/kernel/probes/simulate-insn.h |  3 +-
 arch/arm64/kernel/probes/uprobes.c       | 33 +++++++++
 kernel/events/uprobes.c                  |  2 +-
 8 files changed, 171 insertions(+), 54 deletions(-)

-- 
2.50.1



^ permalink raw reply	[flat|nested] 10+ messages in thread

end of thread, other threads:[~2025-08-20 22:01 UTC | newest]

Thread overview: 10+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-08-18 21:34 [PATCH v6 0/7] arm64: Enable UPROBES with GCS Jeremy Linton
2025-08-18 21:34 ` [PATCH v6 1/7] arm64: probes: Break ret out from bl/blr Jeremy Linton
2025-08-18 21:34 ` [PATCH v6 2/7] arm64: uaccess: Move existing GCS accessors definitions to gcs.h Jeremy Linton
2025-08-20 15:25   ` Mark Brown
2025-08-18 21:34 ` [PATCH v6 3/7] arm64: uaccess: Add additional userspace GCS accessors Jeremy Linton
2025-08-20 17:24   ` Mark Brown
2025-08-18 21:34 ` [PATCH v6 4/7] arm64: probes: Add GCS support to bl/blr/ret Jeremy Linton
2025-08-18 21:34 ` [PATCH v6 5/7] arm64: uprobes: Add GCS support to uretprobes Jeremy Linton
2025-08-18 21:34 ` [PATCH v6 6/7] arm64: Kconfig: Remove GCS restrictions on UPROBES Jeremy Linton
2025-08-18 21:34 ` [PATCH v6 7/7] uprobes: uprobe_warn should use passed task Jeremy Linton

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).