From nobody Fri Dec 19 08:11:48 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 99E3B314A74; Fri, 17 Oct 2025 10:09:04 +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=1760695746; cv=none; b=q+wttXwqid+4TyKNq7Q5YCCaq0p1Nw/tflU8fjGgmWkipRk3GG1yVWgoD6KDaNGm9ibjfM/EFsLtj9b2EfFiCjcawC1iBufvWwfpO9DiBFHxAzMQuEqBKNa8caHxFwcD8Bq2YIEOCYl2O3Am7pMerK/zYu5vVyiPjqrqZfy/1f8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760695746; c=relaxed/simple; bh=kv2agbdsqIbzMLDcTPxxSBLHwg3H9gA4/g6IZ/c2ULk=; h=Message-ID:From:To:Cc:Subject:References:MIME-Version: Content-Type:Date; b=sxm/Kwa5cxjaz/coPKCdVduVV6iVhRsPlUSG/STVq4LaNz2jbgV2SsNwCE/nPXOaeXM/bHx7HhUe3lwV4b1RRVLCzwjZinZdUHQFS5tW8KmITLKNSqzIp5o2O/h4kH5SvTAcEemLm/InKLJTXyJdoOLD2iWVuBNnlUYEaZvdyNI= 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=MnLnslQ4; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=rg0WPyLq; 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="MnLnslQ4"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="rg0WPyLq" Message-ID: <20251017093030.064701062@linutronix.de> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1760695743; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=DNQHcterXWXQuFWR5KPGbkzD3Sh/vJk9lLVEwO1xPSA=; b=MnLnslQ4RTsV85Q3CoH24lxHMQcF21HKHrtG7EOggVFlERWiVpTDR1OV7BLIIXpp85tyM9 I7IoqOHCLIqnPvnSVsWVb/Tu2jQui1WDunh2r7Qwge4EsFLfN8gkhQuolZ3E+cyqEV0YOw 6YqRd4+Xv0RBvQT1MNCkfK6e1IcQ8AumHt6pvIbojy2QtqkEaPYDHqHAea5RkXNWGyEpjl 7xQHleplT3cA3JY0wM9+v9hUdjev9y6y1EgIEzbKs5vYyU4M0DvNL1MGJvittYUZPuSAbA 0ZX2f3AXVPL23vcIPhkezJfXaQwQ3oOGHCYt8SH/2Beh0cStIp1WXsGlFtUGeg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1760695743; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: references:references; bh=DNQHcterXWXQuFWR5KPGbkzD3Sh/vJk9lLVEwO1xPSA=; b=rg0WPyLqAanfBxT81ThSaB9BbJy7x27baok62rRyXXmPsoM3tIHAgK3ol6nAR0EDXBfInK mTIojW6IJ53yd1Cw== From: Thomas Gleixner To: LKML Cc: Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , linuxppc-dev@lists.ozlabs.org, kernel test robot , Russell King , linux-arm-kernel@lists.infradead.org, Linus Torvalds , x86@kernel.org, Paul Walmsley , Palmer Dabbelt , linux-riscv@lists.infradead.org, Heiko Carstens , Christian Borntraeger , Sven Schnelle , linux-s390@vger.kernel.org, Mathieu Desnoyers , Andrew Cooper , Julia Lawall , Nicolas Palix , Peter Zijlstra , Darren Hart , Davidlohr Bueso , =?UTF-8?q?Andr=C3=A9=20Almeida?= , Alexander Viro , Christian Brauner , Jan Kara , linux-fsdevel@vger.kernel.org Subject: [patch V3 04/12] powerpc/uaccess: Use unsafe wrappers for ASM GOTO References: <20251017085938.150569636@linutronix.de> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Date: Fri, 17 Oct 2025 12:09:02 +0200 (CEST) Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" ASM GOTO is miscompiled by GCC when it is used inside a auto cleanup scope: bool foo(u32 __user *p, u32 val) { scoped_guard(pagefault) unsafe_put_user(val, p, efault); return true; efault: return false; } It ends up leaking the pagefault disable counter in the fault path. clang at least fails the build. Rename unsafe_*_user() to arch_unsafe_*_user() which makes the generic uaccess header wrap it with a local label that makes both compilers emit correct code. Same for the kernel_nofault() variants. Signed-off-by: Thomas Gleixner Cc: Madhavan Srinivasan Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: linuxppc-dev@lists.ozlabs.org --- arch/powerpc/include/asm/uaccess.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/powerpc/include/asm/uaccess.h +++ b/arch/powerpc/include/asm/uaccess.h @@ -451,7 +451,7 @@ user_write_access_begin(const void __use #define user_write_access_begin user_write_access_begin #define user_write_access_end prevent_current_write_to_user =20 -#define unsafe_get_user(x, p, e) do { \ +#define arch_unsafe_get_user(x, p, e) do { \ __long_type(*(p)) __gu_val; \ __typeof__(*(p)) __user *__gu_addr =3D (p); \ \ @@ -459,7 +459,7 @@ user_write_access_begin(const void __use (x) =3D (__typeof__(*(p)))__gu_val; \ } while (0) =20 -#define unsafe_put_user(x, p, e) \ +#define arch_unsafe_put_user(x, p, e) \ __put_user_size_goto((__typeof__(*(p)))(x), (p), sizeof(*(p)), e) =20 #define unsafe_copy_from_user(d, s, l, e) \ @@ -504,11 +504,11 @@ do { \ unsafe_put_user(*(u8*)(_src + _i), (u8 __user *)(_dst + _i), e); \ } while (0) =20 -#define __get_kernel_nofault(dst, src, type, err_label) \ +#define arch_get_kernel_nofault(dst, src, type, err_label) \ __get_user_size_goto(*((type *)(dst)), \ (__force type __user *)(src), sizeof(type), err_label) =20 -#define __put_kernel_nofault(dst, src, type, err_label) \ +#define arch_put_kernel_nofault(dst, src, type, err_label) \ __put_user_size_goto(*((type *)(src)), \ (__force type __user *)(dst), sizeof(type), err_label)