linux-kernel - [PATCH AUTOSEL 6.2 18/20] asm-generic/io.h: suppress endianness warnings for readq() and writeq()

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

Message-Id: <20230413023601.74410-18-sashal@kernel.org>
Date:   Wed, 12 Apr 2023 22:35:56 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Vladimir Oltean <vladimir.oltean@....com>,
        Arnd Bergmann <arnd@...db.de>,
        Jonathan Cameron <Jonathan.Cameron@...wei.com>,
        Sasha Levin <sashal@...nel.org>, linux-arch@...r.kernel.org
Subject: [PATCH AUTOSEL 6.2 18/20] asm-generic/io.h: suppress endianness warnings for readq() and writeq()

From: Vladimir Oltean <vladimir.oltean@....com>

[ Upstream commit d564fa1ff19e893e2971d66e5c8f49dc1cdc8ffc ]

Commit c1d55d50139b ("asm-generic/io.h: Fix sparse warnings on
big-endian architectures") missed fixing the 64-bit accessors.

Arnd explains in the attached link why the casts are necessary, even if
__raw_readq() and __raw_writeq() do not take endian-specific types.

Link: https://lore.kernel.org/lkml/9105d6fc-880b-4734-857d-e3d30b87ccf6@app.fastmail.com/
Suggested-by: Arnd Bergmann <arnd@...db.de>
Signed-off-by: Vladimir Oltean <vladimir.oltean@....com>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@...wei.com>
Signed-off-by: Arnd Bergmann <arnd@...db.de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 include/asm-generic/io.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 4c44a29b5e8ef..d78c3056c98f9 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -236,7 +236,7 @@ static inline u64 readq(const volatile void __iomem *addr)
 
 	log_read_mmio(64, addr, _THIS_IP_, _RET_IP_);
 	__io_br();
-	val = __le64_to_cpu(__raw_readq(addr));
+	val = __le64_to_cpu((__le64 __force)__raw_readq(addr));
 	__io_ar(val);
 	log_post_read_mmio(val, 64, addr, _THIS_IP_, _RET_IP_);
 	return val;
@@ -287,7 +287,7 @@ static inline void writeq(u64 value, volatile void __iomem *addr)
 {
 	log_write_mmio(value, 64, addr, _THIS_IP_, _RET_IP_);
 	__io_bw();
-	__raw_writeq(__cpu_to_le64(value), addr);
+	__raw_writeq((u64 __force)__cpu_to_le64(value), addr);
 	__io_aw();
 	log_post_write_mmio(value, 64, addr, _THIS_IP_, _RET_IP_);
 }
-- 
2.39.2