We use the following command to online a memory_block:
echo online|online_kernel|online_movable >
/sys/devices/system/memory/memoryXXX/state
But, if we do the following:
echo online_fhsjkghfkd > /sys/devices/system/memory/memoryXXX/state
the block will also be onlined.
This is because the following code in store_mem_state() does not compare the
whole string,
but only the prefix of the string.
store_mem_state()
{
......
328 if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
Here, only compare the first 13 letters of the string. If we give
"online_kernelXXXXXX",
it will be recognized as online_kernel, which is incorrect.
329 online_type = ONLINE_KERNEL;
330 else if (!strncmp(buf, "online_movable", min_t(int, count, 14)))
We have the same problem here,
331 online_type = ONLINE_MOVABLE;
332 else if (!strncmp(buf, "online", min_t(int, count, 6)))
here,
(Here is more problematic. If we give online_movalbe, which is a typo of
online_movable,
it will be recognized as online without noticing the author.)
333 online_type = ONLINE_KEEP;
334 else if (!strncmp(buf, "offline", min_t(int, count, 7)))
and here.
335 online_type = -1;
336 else {
337 ret = -EINVAL;
338 goto err;
339 }
......
}
This patch fix this problem by using sysfs_streq() to compare the whole string.
Reported-by: Hu Tao <hu...@cn.fujitsu.com>
Signed-off-by: Tang Chen <tangc...@cn.fujitsu.com>
---
change log v1 -> v2:
Following Andrew's suggestion, use sysfs_streq() to compare the whole
string
so that we can simplify the code.
---
---
drivers/base/memory.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index bece691..fa664b9 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -325,13 +325,13 @@ store_mem_state(struct device *dev,
if (ret)
return ret;
- if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
+ if (sysfs_streq(buf, "online_kernel"))
online_type = ONLINE_KERNEL;
- else if (!strncmp(buf, "online_movable", min_t(int, count, 14)))
+ else if (sysfs_streq(buf, "online_movable"))
online_type = ONLINE_MOVABLE;
- else if (!strncmp(buf, "online", min_t(int, count, 6)))
+ else if (sysfs_streq(buf, "online"))
online_type = ONLINE_KEEP;
- else if (!strncmp(buf, "offline", min_t(int, count, 7)))
+ else if (sysfs_streq(buf, "offline"))
online_type = -1;
else {
ret = -EINVAL;
--
1.8.3.1
--
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