Linux s390 Architecture development
 help / color / mirror / Atom feed
From: sashiko-bot@kernel.org
To: "K Prateek Nayak" <kprateek.nayak@amd.com>
Cc: linux-s390@vger.kernel.org,
	"Alexander Gordeev" <agordeev@linux.ibm.com>,
	"Vasily Gorbik" <gor@linux.ibm.com>,
	"Heiko Carstens" <hca@linux.ibm.com>
Subject: Re: [PATCH v6 2/8] arm64/runtime-const: Use aarch64_insn_patch_text_nosync() for patching
Date: Tue, 28 Jul 2026 05:35:49 +0000	[thread overview]
Message-ID: <20260728053549.B3B401F000E9@smtp.kernel.org> (raw)
In-Reply-To: <20260728052540.4728-3-kprateek.nayak@amd.com>

> The current scheme to directly patch the kernel text for runtime
> constants runs into the following issue with futex adapted to using
> runtime constants on arm64:
> 
>   Unable to handle kernel write to read-only memory at virtual address ...
> 
> The pc points to the *p assignment in the following call chain:
> 
>   futex_init()
>     runtime_const_init(shift, __futex_shift)
>       __runtime_fixup_shift()
>         *p = cpu_to_le32(insn);
> 
> which suggests that core_initcall() is too late to patch the kernel text
> directly unlike the "d_hash_shift" which is initialized during
> [ ... ]
> 
> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
> Reviewed-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
> Tested-by: Charlie Jenkins <thecharlesjenkins@gmail.com>
> Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>

Sashiko has reviewed this patch and found no issues. It looks great!

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20260728052540.4728-1-kprateek.nayak@amd.com?part=2


  reply	other threads:[~2026-07-28  5:35 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-28  5:25 [PATCH v6 0/8] futex: Use runtime constants for futex_hash computation K Prateek Nayak
2026-07-28  5:25 ` [PATCH v6 1/8] x86/runtime-const: Introduce runtime_const_mask_32() K Prateek Nayak
2026-07-28  5:37   ` sashiko-bot
2026-07-28  8:21     ` K Prateek Nayak
2026-07-28  5:25 ` [PATCH v6 2/8] arm64/runtime-const: Use aarch64_insn_patch_text_nosync() for patching K Prateek Nayak
2026-07-28  5:35   ` sashiko-bot [this message]
2026-07-28  5:25 ` [PATCH v6 3/8] arm64/runtime-const: Introduce runtime_const_mask_32() K Prateek Nayak
2026-07-28  5:36   ` sashiko-bot
2026-07-28  5:25 ` [PATCH v6 4/8] riscv/runtime-const: Replace open-coded placeholder with RUNTIME_MAGIC K Prateek Nayak
2026-07-28  5:34   ` sashiko-bot
2026-07-28  5:25 ` [PATCH v6 5/8] riscv/runtime-const: Introduce runtime_const_mask_32() K Prateek Nayak
2026-07-28  5:38   ` sashiko-bot
2026-07-28  5:25 ` [PATCH v6 6/8] s390/runtime-const: " K Prateek Nayak
2026-07-28  5:36   ` sashiko-bot
2026-07-28  5:25 ` [PATCH v6 7/8] asm-generic/runtime-const: Add dummy runtime_const_mask_32() K Prateek Nayak
2026-07-28  5:34   ` sashiko-bot
2026-07-28  5:25 ` [PATCH v6 8/8] futex: Use runtime constants for __futex_hash() hot path K Prateek Nayak
2026-07-28  5:42   ` sashiko-bot
2026-07-28 10:46   ` Peter Zijlstra
2026-07-28 11:08     ` Peter Zijlstra

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20260728053549.B3B401F000E9@smtp.kernel.org \
    --to=sashiko-bot@kernel.org \
    --cc=agordeev@linux.ibm.com \
    --cc=gor@linux.ibm.com \
    --cc=hca@linux.ibm.com \
    --cc=kprateek.nayak@amd.com \
    --cc=linux-s390@vger.kernel.org \
    --cc=sashiko-reviews@lists.linux.dev \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox