linux-kernel - Re: [PATCH v2 1/3] arm64/sme: Support disabling streaming mode via ptrace on SME only systems

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <20251029152330.155394-1-david.spickett@linaro.org>
Date: Wed, 29 Oct 2025 15:23:30 +0000
From: David Spickett <david.spickett@...aro.org>
To: broonie@...nel.org
Cc: catalin.marinas@....com,
	corbet@....net,
	david.spickett@....com,
	linux-arm-kernel@...ts.infradead.org,
	linux-doc@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-kselftest@...r.kernel.org,
	luis.machado.foss@...il.com,
	mark.rutland@....com,
	oleg@...hat.com,
	shuah@...nel.org,
	thiago.bauermann@...aro.org,
	will@...nel.org,
	David Spickett <david.spickett@...aro.org>
Subject: Re: [PATCH v2 1/3] arm64/sme: Support disabling streaming mode via ptrace on SME only systems

I have put the LLDB changes for this into review.
We are tracking SME only support in this issue:
https://github.com/llvm/llvm-project/issues/138717

The PRs that relate to these kernel changes are
listed in this comment:
https://github.com/llvm/llvm-project/issues/138717#issuecomment-3456979166

LLDB's use case for this new ptrace feature is to restore
process state after expression evaluation takes a process
from non-streaming to streaming mode. We have a specific
code path to handle that restoration, and it was not a
problem to integrate this new ptrace feature.

I have proven with testcases that LLDB can restore
any streaming mode/ZA/streaming vector length
combination, starting from any other combination.

The LLDB changes will remain in review until if/when
these kernel changes are accepted. I expect LLDB
reviewers will be ok approving changes on the condition
that I wait for the kernel side before merging.

I expect LLDB review to take some time, likely a month,
due to the availability of reviewers at this time.

Reviewed-by: David Spickett <david.spickett@...aro.org>