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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id a12sm7138426pfr.44.2020.06.19.20.30.18 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 Jun 2020 20:30:20 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Nick Desaulniers , Linus Torvalds , Miguel Ojeda , Alexander Potapenko , Joe Perches , Andy Whitcroft , x86@kernel.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, b43-dev@lists.infradead.org, netdev@vger.kernel.org, linux-doc@vger.kernel.org, linux-wireless@vger.kernel.org, linux-ide@vger.kernel.org, linux-clk@vger.kernel.org, linux-spi@vger.kernel.org, linux-mm@kvack.org, clang-built-linux@googlegroups.com Subject: [PATCH v2 06/16] ide: Remove uninitialized_var() usage Date: Fri, 19 Jun 2020 20:29:57 -0700 Message-Id: <20200620033007.1444705-7-keescook@chromium.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200620033007.1444705-1-keescook@chromium.org> References: <20200620033007.1444705-1-keescook@chromium.org> MIME-Version: 1.0 Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Using uninitialized_var() is dangerous as it papers over real bugs[1] (or can in the future), and suppresses unrelated compiler warnings (e.g. "unused variable"). If the compiler thinks it is uninitialized, either simply initialize the variable or make compiler changes. As a precursor to removing[2] this[3] macro[4], just remove this variable since it was actually unused: drivers/ide/ide-taskfile.c:232:34: warning: unused variable 'flags' [-Wunused-variable] unsigned long uninitialized_var(flags); ^ [1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/ [2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/ [3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/ [4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/ Fixes: ce1e518190ea ("ide: don't disable interrupts during kmap_atomic()") Reviewed-by: Nick Desaulniers Signed-off-by: Kees Cook --- drivers/ide/ide-taskfile.c | 1 - 1 file changed, 1 deletion(-) diff --git a/drivers/ide/ide-taskfile.c b/drivers/ide/ide-taskfile.c index aab6a10435b6..a26f85ab58a9 100644 --- a/drivers/ide/ide-taskfile.c +++ b/drivers/ide/ide-taskfile.c @@ -229,7 +229,6 @@ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd, ide_hwif_t *hwif = drive->hwif; struct scatterlist *sg = hwif->sg_table; struct scatterlist *cursg = cmd->cursg; - unsigned long uninitialized_var(flags); struct page *page; unsigned int offset; u8 *buf;