From: Xianting Tian <xianting.tian@linux.alibaba.com>
To: gregkh@linuxfoundation.org, jirislaby@kernel.org,
amit@kernel.org, arnd@arndb.de, osandov@fb.com
Cc: shile.zhang@linux.alibaba.com, linuxppc-dev@lists.ozlabs.org,
virtualization@lists.linux-foundation.org,
linux-kernel@vger.kernel.org,
Xianting Tian <xianting.tian@linux.alibaba.com>
Subject: [PATCH v8 3/3] virtio-console: remove unnecessary kmemdup()
Date: Wed, 18 Aug 2021 16:21:22 +0800 [thread overview]
Message-ID: <20210818082122.166881-4-xianting.tian@linux.alibaba.com> (raw)
In-Reply-To: <20210818082122.166881-1-xianting.tian@linux.alibaba.com>
This revert commit c4baad5029 ("virtio-console: avoid DMA from stack")
hvc framework will never pass stack memory to the put_chars() function,
So the calling of kmemdup() is unnecessary, we can remove it.
Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com>
Reviewed-by: Shile Zhang <shile.zhang@linux.alibaba.com>
---
drivers/char/virtio_console.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 7eaf303a7..4ed3ffb1d 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1117,8 +1117,6 @@ static int put_chars(u32 vtermno, const char *buf, int count)
{
struct port *port;
struct scatterlist sg[1];
- void *data;
- int ret;
if (unlikely(early_put_chars))
return early_put_chars(vtermno, buf, count);
@@ -1127,14 +1125,8 @@ static int put_chars(u32 vtermno, const char *buf, int count)
if (!port)
return -EPIPE;
- data = kmemdup(buf, count, GFP_ATOMIC);
- if (!data)
- return -ENOMEM;
-
- sg_init_one(sg, data, count);
- ret = __send_to_port(port, sg, 1, count, data, false);
- kfree(data);
- return ret;
+ sg_init_one(sg, buf, count);
+ return __send_to_port(port, sg, 1, count, (void *)buf, false);
}
/*
--
2.17.1
prev parent reply other threads:[~2021-08-18 8:22 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-18 8:21 [PATCH v8 0/3] make hvc pass dma capable memory to its backend Xianting Tian
2021-08-18 8:21 ` [PATCH v8 1/3] tty: hvc: use correct dma alignment size Xianting Tian
2021-08-18 8:21 ` [PATCH v8 2/3] tty: hvc: pass DMA capable memory to put_chars() Xianting Tian
2021-08-18 11:03 ` kernel test robot
2021-08-18 17:41 ` kernel test robot
2021-08-20 6:49 ` Daniel Axtens
2021-08-20 8:43 ` Xianting TIan
2021-09-18 12:32 ` Xianting Tian
2021-09-18 12:40 ` Greg KH
2021-09-18 12:47 ` Xianting Tian
2021-08-20 12:34 ` Michael Ellerman
2021-08-18 8:21 ` Xianting Tian [this message]
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