From nobody Sun Dec 14 18:11:36 2025 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 42191330317; Wed, 29 Oct 2025 10:23:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761733423; cv=none; b=BsKtiIleHPNXwOg59vAZlBAv2R5RGBogTjVcTvPfa4E49/GtT0F1gXN16V6592sBFF3TFqONQPnuULYUQ2zdEcwadPuE0aJzRxNt1qwxLHpoJ/W8EJl06kfTiQZFt1Ouwap9SE95PLbyrkg7Z/JpJ9p/UeJIIpkJ3+BlVMHseB0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761733423; c=relaxed/simple; bh=ySdimN+QkzL18rGoyml6zeGufdwfHDxQgcpKZwQ0gDc=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=GkHsj49AfYq5w7V3d606jKUt/bUMHGsOwDwNY2IE3FiHC7r4++R9oMLYauJyKhvCDuqeE2WqSZ3kLX5SlEBMAsKdHuYd0m5hM8UFMbJ+BYu5drJCzdR4Gt8q3KX5+fPHN5a+JEopxBzq6GaDZHZXNnb5w4inHKyZ2xHWEiMLRaw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=WSGcQdND; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=z++6zyAV; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="WSGcQdND"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="z++6zyAV" Date: Wed, 29 Oct 2025 10:23:37 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1761733419; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/pC1X/B1pNmEbeP1AK2hapn4kJzgWQN8MeMXjzYeh3Q=; b=WSGcQdNDa1/lllu4erd7+5SAfT62ouPsZEap/GXdw/Jcoeq5FrR3KGrqIihGVFdkfgPffr cEkxRlzIhFb/xGW4mVwR8fpYrxUgpT7AqQH7rO4fOChDwFbwbHRox2AowgljJvGmIFLWiT mQIbGMdQIggtt29j+oYFgAz6pvY2eHRUZfujS+B8o7mKDOg52ON01c+mUA9xnSxn+UbCsz DSMTGwWzZJwhvdGvWreojLTHYKYkkqngLvfEEl5QE59Xkp8kdTsSVcs+A6XVy/j4NlZ+Cx SxYkVOYnoGAf7+zjbBjkWn7c8faPJOJ5Cqwy98oOA1HGeLlyrIoVpX1lppoyaA== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1761733419; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/pC1X/B1pNmEbeP1AK2hapn4kJzgWQN8MeMXjzYeh3Q=; b=z++6zyAViq292ACpQXo0dN13pTxdzOVgGJYiWdafUWWDaaZdhq0M1Q9RUF3n/rISUaK327 271tBQHiOG6v7tDQ== From: "tip-bot2 for Thomas Gleixner" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: core/rseq] rseq: Use static branch for syscall exit debug when GENERIC_IRQ_ENTRY=y Cc: Thomas Gleixner , "Peter Zijlstra (Intel)" , Mathieu Desnoyers , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20251027084307.333440475@linutronix.de> References: <20251027084307.333440475@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <176173341760.2601451.1484495948667542485.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the core/rseq branch of tip: Commit-ID: 785637e834310e88ce00cb9eed2ba7ba03ea561d Gitweb: https://git.kernel.org/tip/785637e834310e88ce00cb9eed2ba7ba0= 3ea561d Author: Thomas Gleixner AuthorDate: Mon, 27 Oct 2025 09:45:05 +01:00 Committer: Peter Zijlstra CommitterDate: Wed, 29 Oct 2025 11:07:17 +01:00 rseq: Use static branch for syscall exit debug when GENERIC_IRQ_ENTRY=3Dy Make the syscall exit debug mechanism available via the static branch on architectures which utilize the generic entry code. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Mathieu Desnoyers Link: https://patch.msgid.link/20251027084307.333440475@linutronix.de --- include/linux/entry-common.h | 2 +- include/linux/rseq_entry.h | 9 +++++++++ kernel/rseq.c | 10 ++++++++-- 3 files changed, 18 insertions(+), 3 deletions(-) diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index 75b194c..d967184 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -146,7 +146,7 @@ static __always_inline void syscall_exit_to_user_mode_w= ork(struct pt_regs *regs) local_irq_enable(); } =20 - rseq_syscall(regs); + rseq_debug_syscall_return(regs); =20 /* * Do one-time syscall specific work. If these work items are diff --git a/include/linux/rseq_entry.h b/include/linux/rseq_entry.h index 5bdcf5b..fb53a6f 100644 --- a/include/linux/rseq_entry.h +++ b/include/linux/rseq_entry.h @@ -296,9 +296,18 @@ static __always_inline void rseq_exit_to_user_mode(voi= d) ev->events =3D 0; } =20 +void __rseq_debug_syscall_return(struct pt_regs *regs); + +static inline void rseq_debug_syscall_return(struct pt_regs *regs) +{ + if (static_branch_unlikely(&rseq_debug_enabled)) + __rseq_debug_syscall_return(regs); +} + #else /* CONFIG_RSEQ */ static inline void rseq_note_user_irq_entry(void) { } static inline void rseq_exit_to_user_mode(void) { } +static inline void rseq_debug_syscall_return(struct pt_regs *regs) { } #endif /* !CONFIG_RSEQ */ =20 #endif /* _LINUX_RSEQ_ENTRY_H */ diff --git a/kernel/rseq.c b/kernel/rseq.c index 07d9fa7..5f21270 100644 --- a/kernel/rseq.c +++ b/kernel/rseq.c @@ -473,12 +473,11 @@ error: force_sigsegv(sig); } =20 -#ifdef CONFIG_DEBUG_RSEQ /* * Terminate the process if a syscall is issued within a restartable * sequence. */ -void rseq_syscall(struct pt_regs *regs) +void __rseq_debug_syscall_return(struct pt_regs *regs) { struct task_struct *t =3D current; u64 csaddr; @@ -496,6 +495,13 @@ void rseq_syscall(struct pt_regs *regs) fail: force_sig(SIGSEGV); } + +#ifdef CONFIG_DEBUG_RSEQ +/* Kept around to keep GENERIC_ENTRY=3Dn architectures supported. */ +void rseq_syscall(struct pt_regs *regs) +{ + __rseq_debug_syscall_return(regs); +} #endif =20 /*