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[173.164.112.133]) by smtp.gmail.com with ESMTPSA id b77-v6sm28297879pfm.3.2018.11.01.16.52.06 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Thu, 01 Nov 2018 16:52:08 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Joel Fernandes , Anton Vorontsov , Colin Cross , Tony Luck Subject: [PATCH 7/8] pstore: Remove needless lock during console writes Date: Thu, 1 Nov 2018 16:51:59 -0700 Message-Id: <20181101235200.28584-8-keescook@chromium.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181101235200.28584-1-keescook@chromium.org> References: <20181101235200.28584-1-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since commit 70ad35db3321 ("pstore: Convert console write to use ->write_buf"), the console writer does not use the preallocated crash dump buffer any more, so there is no reason to perform locking around it. Signed-off-by: Kees Cook --- fs/pstore/platform.c | 29 ++++++----------------------- 1 file changed, 6 insertions(+), 23 deletions(-) diff --git a/fs/pstore/platform.c b/fs/pstore/platform.c index a956c7bc3f67..32340e7dd6a5 100644 --- a/fs/pstore/platform.c +++ b/fs/pstore/platform.c @@ -461,31 +461,14 @@ static void pstore_unregister_kmsg(void) #ifdef CONFIG_PSTORE_CONSOLE static void pstore_console_write(struct console *con, const char *s, unsigned c) { - const char *e = s + c; + struct pstore_record record; - while (s < e) { - struct pstore_record record; - unsigned long flags; - - pstore_record_init(&record, psinfo); - record.type = PSTORE_TYPE_CONSOLE; - - if (c > psinfo->bufsize) - c = psinfo->bufsize; + pstore_record_init(&record, psinfo); + record.type = PSTORE_TYPE_CONSOLE; - if (oops_in_progress) { - if (!spin_trylock_irqsave(&psinfo->buf_lock, flags)) - break; - } else { - spin_lock_irqsave(&psinfo->buf_lock, flags); - } - record.buf = (char *)s; - record.size = c; - psinfo->write(&record); - spin_unlock_irqrestore(&psinfo->buf_lock, flags); - s += c; - c = e - s; - } + record.buf = (char *)s; + record.size = c; + psinfo->write(&record); } static struct console pstore_console = { -- 2.17.1