[PATCH 5.4 070/434] ath10k: fix backtrace on coredump

Greg Kroah-Hartman
2019-12-29T18:10:39Z

From: Anilkumar Kolli <akolli@codeaurora.org>

[ Upstream commit d98ddae85a4a57124f87960047b1b6419312147f ]

In a multiradio board with one QCA9984 and one AR9987
after enabling the crashdump with module parameter
coredump_mask=7, below backtrace is seen.

vmalloc: allocation failure: 0 bytes
kworker/u4:0: page allocation failure: order:0, mode:0x80d2
CPU: 0 PID: 6 Comm: kworker/u4:0 Not tainted 3.14.77 #130
Workqueue: ath10k_wq ath10k_core_register_work [ath10k_core]
(unwind_backtrace) from [<c021abf8>] (show_stack+0x10/0x14)
(dump_stack+0x80/0xa0)
(warn_alloc_failed+0xd0/0xfc)
(__vmalloc_node_range+0x1b4/0x1d8)
(__vmalloc_node+0x34/0x40)
(vzalloc+0x24/0x30)
(ath10k_coredump_register+0x6c/0x88 [ath10k_core])
(ath10k_core_register_work+0x350/0xb34 [ath10k_core])
(process_one_work+0x20c/0x32c)
(worker_thread+0x228/0x360)

This is due to ath10k_hw_mem_layout is not defined for AR9987.
For coredump undefined hw ramdump_size is 0.
Check for the ramdump_size before allocation memory.

Tested on: AR9987, QCA9984
FW version: 10.4-3.9.0.2-00044

Signed-off-by: Anilkumar Kolli <akolli@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/ath/ath10k/coredump.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/ath/ath10k/coredump.c b/drivers/net/wireless/ath/ath10k/coredump.c
index b6d2932383cf..1cfe75a2d0c3 100644
--- a/drivers/net/wireless/ath/ath10k/coredump.c
+++ b/drivers/net/wireless/ath/ath10k/coredump.c
@@ -1208,9 +1208,11 @@ static struct ath10k_dump_file_data *ath10k_coredump_build(struct ath10k *ar)
dump_tlv = (struct ath10k_tlv_dump_data *)(buf + sofar);
dump_tlv->type = cpu_to_le32(ATH10K_FW_CRASH_DUMP_RAM_DATA);
dump_tlv->tlv_len = cpu_to_le32(crash_data->ramdump_buf_len);
- memcpy(dump_tlv->tlv_data, crash_data->ramdump_buf,
- crash_data->ramdump_buf_len);
- sofar += sizeof(*dump_tlv) + crash_data->ramdump_buf_len;
+ if (crash_data->ramdump_buf_len) {
+ memcpy(dump_tlv->tlv_data, crash_data->ramdump_buf,
+ crash_data->ramdump_buf_len);
+ sofar += sizeof(*dump_tlv) + crash_data->ramdump_buf_len;
+ }
}

mutex_unlock(&ar->dump_mutex);
@@ -1257,6 +1259,9 @@ int ath10k_coredump_register(struct ath10k *ar)
if (test_bit(ATH10K_FW_CRASH_DUMP_RAM_DATA, &ath10k_coredump_mask)) {
crash_data->ramdump_buf_len = ath10k_coredump_get_ramdump_size(ar);

+ if (!crash_data->ramdump_buf_len)
+ return 0;
+
crash_data->ramdump_buf = vzalloc(crash_data->ramdump_buf_len);
if (!crash_data->ramdump_buf)
return -ENOMEM;
--
2.20.1