[PATCH V2 08/10] Drivers: hv: fcopy: dynamically allocate smsg_out in fcopy_send_data()

From: K. Y. Srinivasan
Date: Thu Jun 04 2015 - 18:06:00 EST


From: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>

struct hv_start_fcopy is too big to be on stack on i386, the following
warning is reported:

>> drivers/hv/hv_fcopy.c:159:1: warning: the frame size of 1088 bytes is larger than 1024 bytes [-Wframe-larger-than=]

Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx>
Signed-off-by: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: K. Y. Srinivasan <kys@xxxxxxxxxxxxx>
---
drivers/hv/hv_fcopy.c | 21 +++++++++++++--------
1 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c
index b50dd33..db4b887 100644
--- a/drivers/hv/hv_fcopy.c
+++ b/drivers/hv/hv_fcopy.c
@@ -116,7 +116,7 @@ static int fcopy_handle_handshake(u32 version)

static void fcopy_send_data(struct work_struct *dummy)
{
- struct hv_start_fcopy smsg_out;
+ struct hv_start_fcopy *smsg_out = NULL;
int operation = fcopy_transaction.fcopy_msg->operation;
struct hv_start_fcopy *smsg_in;
void *out_src;
@@ -136,21 +136,24 @@ static void fcopy_send_data(struct work_struct *dummy)
switch (operation) {
case START_FILE_COPY:
out_len = sizeof(struct hv_start_fcopy);
- memset(&smsg_out, 0, out_len);
- smsg_out.hdr.operation = operation;
+ smsg_out = kzalloc(sizeof(*smsg_out), GFP_KERNEL);
+ if (!smsg_out)
+ return;
+
+ smsg_out->hdr.operation = operation;
smsg_in = (struct hv_start_fcopy *)fcopy_transaction.fcopy_msg;

utf16s_to_utf8s((wchar_t *)smsg_in->file_name, W_MAX_PATH,
UTF16_LITTLE_ENDIAN,
- (__u8 *)&smsg_out.file_name, W_MAX_PATH - 1);
+ (__u8 *)&smsg_out->file_name, W_MAX_PATH - 1);

utf16s_to_utf8s((wchar_t *)smsg_in->path_name, W_MAX_PATH,
UTF16_LITTLE_ENDIAN,
- (__u8 *)&smsg_out.path_name, W_MAX_PATH - 1);
+ (__u8 *)&smsg_out->path_name, W_MAX_PATH - 1);

- smsg_out.copy_flags = smsg_in->copy_flags;
- smsg_out.file_size = smsg_in->file_size;
- out_src = &smsg_out;
+ smsg_out->copy_flags = smsg_in->copy_flags;
+ smsg_out->file_size = smsg_in->file_size;
+ out_src = smsg_out;
break;

default:
@@ -168,6 +171,8 @@ static void fcopy_send_data(struct work_struct *dummy)
fcopy_transaction.state = HVUTIL_READY;
}
}
+ kfree(smsg_out);
+
return;
}

--
1.7.4.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/