From: Ard Biesheuvel <ardb+git@google.com>
To: linux-efi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org,
linux-arm-kernel@lists.infradead.org,
Ard Biesheuvel <ardb@kernel.org>, Will Deacon <will@kernel.org>,
Mark Rutland <mark.rutland@arm.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Peter Zijlstra <peterz@infradead.org>
Subject: [PATCH v2 4/7] arm64/fpsimd: Don't warn when EFI execution context is preemptible
Date: Fri, 5 Sep 2025 15:30:40 +0200 [thread overview]
Message-ID: <20250905133035.275517-13-ardb+git@google.com> (raw)
In-Reply-To: <20250905133035.275517-9-ardb+git@google.com>
From: Ard Biesheuvel <ardb@kernel.org>
Kernel mode FP/SIMD no longer requires preemption to be disabled, so
only warn on uses of FP/SIMD from preemptible context if the fallback
path is taken for cases where kernel mode NEON would not be allowed
otherwise.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/arm64/kernel/fpsimd.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c
index c37f02d7194e..d26a02ea2bb9 100644
--- a/arch/arm64/kernel/fpsimd.c
+++ b/arch/arm64/kernel/fpsimd.c
@@ -1933,11 +1933,11 @@ void __efi_fpsimd_begin(void)
if (!system_supports_fpsimd())
return;
- WARN_ON(preemptible());
-
if (may_use_simd()) {
kernel_neon_begin();
} else {
+ WARN_ON(preemptible());
+
/*
* If !efi_sve_state, SVE can't be in use yet and doesn't need
* preserving:
--
2.51.0.355.g5224444f11-goog
next prev parent reply other threads:[~2025-09-05 17:26 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-05 13:30 [PATCH v2 0/7] arm64: Make EFI calls preemptible Ard Biesheuvel
2025-09-05 13:30 ` [PATCH v2 1/7] efi: Add missing static initializer for efi_mm::cpus_allowed_lock Ard Biesheuvel
2025-09-05 13:30 ` [PATCH v2 2/7] efi/runtime: Return success/failure from arch_efi_call_virt_setup() Ard Biesheuvel
2025-09-05 13:30 ` [PATCH v2 3/7] efi/runtime: Deal with arch_efi_call_virt_setup() returning failure Ard Biesheuvel
2025-09-05 13:30 ` Ard Biesheuvel [this message]
2025-09-05 13:30 ` [PATCH v2 5/7] arm64/efi: Use a semaphore to protect the EFI stack and FP/SIMD state Ard Biesheuvel
2025-09-05 13:44 ` Peter Zijlstra
2025-09-05 13:54 ` Ard Biesheuvel
2025-09-08 15:37 ` Peter Zijlstra
2025-09-05 13:30 ` [PATCH v2 6/7] arm64/efi: Move uaccess en/disable out of efi_set_pgd() Ard Biesheuvel
2025-09-05 13:30 ` [PATCH v2 7/7] arm64/efi: Call EFI runtime services without disabling preemption Ard Biesheuvel
2025-09-05 15:45 ` [PATCH v2 0/7] arm64: Make EFI calls preemptible Yeoreum Yun
2025-09-15 8:52 ` Sebastian Andrzej Siewior
2025-09-15 9:05 ` Ard Biesheuvel
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=20250905133035.275517-13-ardb+git@google.com \
--to=ardb+git@google.com \
--cc=ardb@kernel.org \
--cc=bigeasy@linutronix.de \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-efi@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=peterz@infradead.org \
--cc=will@kernel.org \
/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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.