2022-06-02 16:01:59

by Duoming Zhou

[permalink] [raw]
Subject: [PATCH v4 0/2] Remove extra param of dev_coredumpv and fix bugs

The first patch removes the extra gfp_t param of dev_coredumpv.
The second patch fix sleep in atomic context bugs of mwifiex
caused by dev_coredumpv.

Duoming Zhou (2):
devcoredump: remove the useless gfp_t parameter in dev_coredumpv
mwifiex: fix sleep in atomic context bugs caused by dev_coredumpv

drivers/base/devcoredump.c | 6 ++----
drivers/bluetooth/btmrvl_sdio.c | 2 +-
drivers/bluetooth/hci_qca.c | 2 +-
drivers/gpu/drm/etnaviv/etnaviv_dump.c | 2 +-
drivers/media/platform/qcom/venus/core.c | 2 +-
drivers/net/can/spi/mcp251xfd/mcp251xfd-dump.c | 2 +-
drivers/net/wireless/ath/ath10k/coredump.c | 2 +-
drivers/net/wireless/ath/wil6210/wil_crash_dump.c | 2 +-
.../net/wireless/broadcom/brcm80211/brcmfmac/debug.c | 2 +-
drivers/net/wireless/marvell/mwifiex/init.c | 10 ++++++----
drivers/net/wireless/marvell/mwifiex/main.c | 3 +--
drivers/net/wireless/marvell/mwifiex/main.h | 2 +-
drivers/net/wireless/marvell/mwifiex/sta_event.c | 6 +++---
drivers/net/wireless/mediatek/mt76/mt7615/mac.c | 3 +--
drivers/net/wireless/mediatek/mt76/mt7921/mac.c | 3 +--
drivers/net/wireless/realtek/rtw88/main.c | 2 +-
drivers/net/wireless/realtek/rtw89/ser.c | 2 +-
drivers/remoteproc/qcom_q6v5_mss.c | 2 +-
drivers/remoteproc/remoteproc_coredump.c | 4 ++--
include/linux/devcoredump.h | 5 ++---
sound/soc/intel/catpt/dsp.c | 2 +-
21 files changed, 31 insertions(+), 35 deletions(-)

--
2.17.1



2022-06-02 17:39:05

by Duoming Zhou

[permalink] [raw]
Subject: [PATCH v4 2/2] mwifiex: fix sleep in atomic context bugs caused by dev_coredumpv

There are sleep in atomic context bugs when uploading device dump
data in mwifiex. The root cause is that dev_coredumpv could not
be used in atomic contexts, because it calls dev_set_name which
include operations that may sleep. The call tree shows execution
paths that could lead to bugs:

(Interrupt context)
fw_dump_timer_fn
mwifiex_upload_device_dump
dev_coredumpv(..., GFP_KERNEL)
dev_coredumpm()
kzalloc(sizeof(*devcd), gfp); //may sleep
dev_set_name
kobject_set_name_vargs
kvasprintf_const(GFP_KERNEL, ...); //may sleep
kstrdup(s, GFP_KERNEL); //may sleep

The corresponding fail log is shown below:

[ 135.275938] usb 1-1: == mwifiex dump information to /sys/class/devcoredump start
[ 135.281029] BUG: sleeping function called from invalid context at include/linux/sched/mm.h:265
...
[ 135.293613] Call Trace:
[ 135.293613] <IRQ>
[ 135.293613] dump_stack_lvl+0x57/0x7d
[ 135.293613] __might_resched.cold+0x138/0x173
[ 135.293613] ? dev_coredumpm+0xca/0x2e0
[ 135.293613] kmem_cache_alloc_trace+0x189/0x1f0
[ 135.293613] ? devcd_match_failing+0x30/0x30
[ 135.293613] dev_coredumpm+0xca/0x2e0
[ 135.293613] ? devcd_freev+0x10/0x10
[ 135.293613] dev_coredumpv+0x1c/0x20
[ 135.293613] ? devcd_match_failing+0x30/0x30
[ 135.293613] mwifiex_upload_device_dump+0x65/0xb0
[ 135.293613] ? mwifiex_dnld_fw+0x1b0/0x1b0
[ 135.293613] call_timer_fn+0x122/0x3d0
[ 135.293613] ? msleep_interruptible+0xb0/0xb0
[ 135.293613] ? lock_downgrade+0x3c0/0x3c0
[ 135.293613] ? __next_timer_interrupt+0x13c/0x160
[ 135.293613] ? lockdep_hardirqs_on_prepare+0xe/0x220
[ 135.293613] ? mwifiex_dnld_fw+0x1b0/0x1b0
[ 135.293613] __run_timers.part.0+0x3f8/0x540
[ 135.293613] ? call_timer_fn+0x3d0/0x3d0
[ 135.293613] ? arch_restore_msi_irqs+0x10/0x10
[ 135.293613] ? lapic_next_event+0x31/0x40
[ 135.293613] run_timer_softirq+0x4f/0xb0
[ 135.293613] __do_softirq+0x1c2/0x651
...
[ 135.293613] RIP: 0010:default_idle+0xb/0x10
[ 135.293613] RSP: 0018:ffff888006317e68 EFLAGS: 00000246
[ 135.293613] RAX: ffffffff82ad8d10 RBX: ffff888006301cc0 RCX: ffffffff82ac90e1
[ 135.293613] RDX: ffffed100d9ff1b4 RSI: ffffffff831ad140 RDI: ffffffff82ad8f20
[ 135.293613] RBP: 0000000000000003 R08: 0000000000000000 R09: ffff88806cff8d9b
[ 135.293613] R10: ffffed100d9ff1b3 R11: 0000000000000001 R12: ffffffff84593410
[ 135.293613] R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff11000c62fd2
...
[ 135.389205] usb 1-1: == mwifiex dump information to /sys/class/devcoredump end

This patch uses delayed work to replace timer and moves the operations
that may sleep into a delayed work in order to mitigate bugs, it was
tested on Marvell 88W8801 chip whose port is usb and the firmware is
usb8801_uapsta.bin. The following is the result after using delayed
work to replace timer.

[ 134.936453] usb 1-1: == mwifiex dump information to /sys/class/devcoredump start
[ 135.043344] usb 1-1: == mwifiex dump information to /sys/class/devcoredump end

As we can see, there is no bug now.

Fixes: f5ecd02a8b20 ("mwifiex: device dump support for usb interface")
Signed-off-by: Duoming Zhou <[email protected]>
---
Changes in v4:
- Use delayed work to replace timer.

drivers/net/wireless/marvell/mwifiex/init.c | 10 ++++++----
drivers/net/wireless/marvell/mwifiex/main.h | 2 +-
drivers/net/wireless/marvell/mwifiex/sta_event.c | 6 +++---
3 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/marvell/mwifiex/init.c b/drivers/net/wireless/marvell/mwifiex/init.c
index 88c72d1827a..3713f3e323f 100644
--- a/drivers/net/wireless/marvell/mwifiex/init.c
+++ b/drivers/net/wireless/marvell/mwifiex/init.c
@@ -63,9 +63,11 @@ static void wakeup_timer_fn(struct timer_list *t)
adapter->if_ops.card_reset(adapter);
}

-static void fw_dump_timer_fn(struct timer_list *t)
+static void fw_dump_work(struct work_struct *work)
{
- struct mwifiex_adapter *adapter = from_timer(adapter, t, devdump_timer);
+ struct mwifiex_adapter *adapter = container_of(work,
+ struct mwifiex_adapter,
+ devdump_work.work);

mwifiex_upload_device_dump(adapter);
}
@@ -321,7 +323,7 @@ static void mwifiex_init_adapter(struct mwifiex_adapter *adapter)
adapter->active_scan_triggered = false;
timer_setup(&adapter->wakeup_timer, wakeup_timer_fn, 0);
adapter->devdump_len = 0;
- timer_setup(&adapter->devdump_timer, fw_dump_timer_fn, 0);
+ INIT_DELAYED_WORK(&adapter->devdump_work, fw_dump_work);
}

/*
@@ -400,7 +402,7 @@ static void
mwifiex_adapter_cleanup(struct mwifiex_adapter *adapter)
{
del_timer(&adapter->wakeup_timer);
- del_timer_sync(&adapter->devdump_timer);
+ cancel_delayed_work_sync(&adapter->devdump_work);
mwifiex_cancel_all_pending_cmd(adapter);
wake_up_interruptible(&adapter->cmd_wait_q.wait);
wake_up_interruptible(&adapter->hs_activate_wait_q);
diff --git a/drivers/net/wireless/marvell/mwifiex/main.h b/drivers/net/wireless/marvell/mwifiex/main.h
index 332dd1c8db3..6530c6ee308 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.h
+++ b/drivers/net/wireless/marvell/mwifiex/main.h
@@ -1055,7 +1055,7 @@ struct mwifiex_adapter {
/* Device dump data/length */
void *devdump_data;
int devdump_len;
- struct timer_list devdump_timer;
+ struct delayed_work devdump_work;

bool ignore_btcoex_events;
};
diff --git a/drivers/net/wireless/marvell/mwifiex/sta_event.c b/drivers/net/wireless/marvell/mwifiex/sta_event.c
index 7d42c5d2dbf..4d93386494c 100644
--- a/drivers/net/wireless/marvell/mwifiex/sta_event.c
+++ b/drivers/net/wireless/marvell/mwifiex/sta_event.c
@@ -623,8 +623,8 @@ mwifiex_fw_dump_info_event(struct mwifiex_private *priv,
* transmission event get lost, in this cornel case,
* user would still get partial of the dump.
*/
- mod_timer(&adapter->devdump_timer,
- jiffies + msecs_to_jiffies(MWIFIEX_TIMER_10S));
+ schedule_delayed_work(&adapter->devdump_work,
+ msecs_to_jiffies(MWIFIEX_TIMER_10S));
}

/* Overflow check */
@@ -643,7 +643,7 @@ mwifiex_fw_dump_info_event(struct mwifiex_private *priv,
return;

upload_dump:
- del_timer_sync(&adapter->devdump_timer);
+ cancel_delayed_work_sync(&adapter->devdump_work);
mwifiex_upload_device_dump(adapter);
}

--
2.17.1


2022-06-02 19:42:33

by Duoming Zhou

[permalink] [raw]
Subject: [PATCH v4 1/2] devcoredump: remove the useless gfp_t parameter in dev_coredumpv

The dev_coredumpv() could not be used in atomic context, because
it calls kvasprintf_const() and kstrdup() with GFP_KERNEL parameter.
The process is shown below:

dev_coredumpv(..., gfp_t gfp)
dev_coredumpm
dev_set_name
kobject_set_name_vargs
kvasprintf_const(GFP_KERNEL, ...); //may sleep
kstrdup(s, GFP_KERNEL); //may sleep

This patch removes gfp_t parameter of dev_coredumpv() and changes the
gfp_t parameter of dev_coredumpm() to GFP_KERNEL in order to show
dev_coredumpv() could not be used in atomic context.

Fixes: 833c95456a70 ("device coredump: add new device coredump class")
Signed-off-by: Duoming Zhou <[email protected]>
---
Changes in v4:
- Drop gfp_t parameter of dev_coredumpv.

drivers/base/devcoredump.c | 6 ++----
drivers/bluetooth/btmrvl_sdio.c | 2 +-
drivers/bluetooth/hci_qca.c | 2 +-
drivers/gpu/drm/etnaviv/etnaviv_dump.c | 2 +-
drivers/media/platform/qcom/venus/core.c | 2 +-
drivers/net/can/spi/mcp251xfd/mcp251xfd-dump.c | 2 +-
drivers/net/wireless/ath/ath10k/coredump.c | 2 +-
drivers/net/wireless/ath/wil6210/wil_crash_dump.c | 2 +-
drivers/net/wireless/broadcom/brcm80211/brcmfmac/debug.c | 2 +-
drivers/net/wireless/marvell/mwifiex/main.c | 3 +--
drivers/net/wireless/mediatek/mt76/mt7615/mac.c | 3 +--
drivers/net/wireless/mediatek/mt76/mt7921/mac.c | 3 +--
drivers/net/wireless/realtek/rtw88/main.c | 2 +-
drivers/net/wireless/realtek/rtw89/ser.c | 2 +-
drivers/remoteproc/qcom_q6v5_mss.c | 2 +-
drivers/remoteproc/remoteproc_coredump.c | 4 ++--
include/linux/devcoredump.h | 5 ++---
sound/soc/intel/catpt/dsp.c | 2 +-
18 files changed, 21 insertions(+), 27 deletions(-)

diff --git a/drivers/base/devcoredump.c b/drivers/base/devcoredump.c
index f4d794d6bb8..5b331e9460e 100644
--- a/drivers/base/devcoredump.c
+++ b/drivers/base/devcoredump.c
@@ -173,15 +173,13 @@ static void devcd_freev(void *data)
* @dev: the struct device for the crashed device
* @data: vmalloc data containing the device coredump
* @datalen: length of the data
- * @gfp: allocation flags
*
* This function takes ownership of the vmalloc'ed data and will free
* it when it is no longer used. See dev_coredumpm() for more information.
*/
-void dev_coredumpv(struct device *dev, void *data, size_t datalen,
- gfp_t gfp)
+void dev_coredumpv(struct device *dev, void *data, size_t datalen)
{
- dev_coredumpm(dev, NULL, data, datalen, gfp, devcd_readv, devcd_freev);
+ dev_coredumpm(dev, NULL, data, datalen, GFP_KERNEL, devcd_readv, devcd_freev);
}
EXPORT_SYMBOL_GPL(dev_coredumpv);

diff --git a/drivers/bluetooth/btmrvl_sdio.c b/drivers/bluetooth/btmrvl_sdio.c
index b8ef66f89fc..9b9728719db 100644
--- a/drivers/bluetooth/btmrvl_sdio.c
+++ b/drivers/bluetooth/btmrvl_sdio.c
@@ -1515,7 +1515,7 @@ static void btmrvl_sdio_coredump(struct device *dev)
/* fw_dump_data will be free in device coredump release function
* after 5 min
*/
- dev_coredumpv(&card->func->dev, fw_dump_data, fw_dump_len, GFP_KERNEL);
+ dev_coredumpv(&card->func->dev, fw_dump_data, fw_dump_len);
BT_INFO("== btmrvl firmware dump to /sys/class/devcoredump end");
}

diff --git a/drivers/bluetooth/hci_qca.c b/drivers/bluetooth/hci_qca.c
index eab34e24d94..2e4074211ae 100644
--- a/drivers/bluetooth/hci_qca.c
+++ b/drivers/bluetooth/hci_qca.c
@@ -1120,7 +1120,7 @@ static void qca_controller_memdump(struct work_struct *work)
qca_memdump->ram_dump_size);
memdump_buf = qca_memdump->memdump_buf_head;
dev_coredumpv(&hu->serdev->dev, memdump_buf,
- qca_memdump->received_dump, GFP_KERNEL);
+ qca_memdump->received_dump);
cancel_delayed_work(&qca->ctrl_memdump_timeout);
kfree(qca->qca_memdump);
qca->qca_memdump = NULL;
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_dump.c b/drivers/gpu/drm/etnaviv/etnaviv_dump.c
index f418e0b7577..519fcb234b3 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_dump.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_dump.c
@@ -225,5 +225,5 @@ void etnaviv_core_dump(struct etnaviv_gem_submit *submit)

etnaviv_core_dump_header(&iter, ETDUMP_BUF_END, iter.data);

- dev_coredumpv(gpu->dev, iter.start, iter.data - iter.start, GFP_KERNEL);
+ dev_coredumpv(gpu->dev, iter.start, iter.data - iter.start);
}
diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
index 877eca12580..db84dfb3fb1 100644
--- a/drivers/media/platform/qcom/venus/core.c
+++ b/drivers/media/platform/qcom/venus/core.c
@@ -49,7 +49,7 @@ static void venus_coredump(struct venus_core *core)

memcpy(data, mem_va, mem_size);
memunmap(mem_va);
- dev_coredumpv(dev, data, mem_size, GFP_KERNEL);
+ dev_coredumpv(dev, data, mem_size);
}

static void venus_event_notify(struct venus_core *core, u32 event)
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-dump.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-dump.c
index c991b30bc9f..fa520ab7c96 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-dump.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-dump.c
@@ -281,5 +281,5 @@ void mcp251xfd_dump(const struct mcp251xfd_priv *priv)
mcp251xfd_dump_end(priv, &iter);

dev_coredumpv(&priv->spi->dev, iter.start,
- iter.data - iter.start, GFP_KERNEL);
+ iter.data - iter.start);
}
diff --git a/drivers/net/wireless/ath/ath10k/coredump.c b/drivers/net/wireless/ath/ath10k/coredump.c
index fe6b6f97a91..dc923706992 100644
--- a/drivers/net/wireless/ath/ath10k/coredump.c
+++ b/drivers/net/wireless/ath/ath10k/coredump.c
@@ -1607,7 +1607,7 @@ int ath10k_coredump_submit(struct ath10k *ar)
return -ENODATA;
}

- dev_coredumpv(ar->dev, dump, le32_to_cpu(dump->len), GFP_KERNEL);
+ dev_coredumpv(ar->dev, dump, le32_to_cpu(dump->len));

return 0;
}
diff --git a/drivers/net/wireless/ath/wil6210/wil_crash_dump.c b/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
index 89c12cb2aaa..79299609dd6 100644
--- a/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
+++ b/drivers/net/wireless/ath/wil6210/wil_crash_dump.c
@@ -117,6 +117,6 @@ void wil_fw_core_dump(struct wil6210_priv *wil)
/* fw_dump_data will be free in device coredump release function
* after 5 min
*/
- dev_coredumpv(wil_to_dev(wil), fw_dump_data, fw_dump_size, GFP_KERNEL);
+ dev_coredumpv(wil_to_dev(wil), fw_dump_data, fw_dump_size);
wil_info(wil, "fw core dumped, size %d bytes\n", fw_dump_size);
}
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/debug.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/debug.c
index eecf8a38d94..87f3652ef3b 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/debug.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/debug.c
@@ -37,7 +37,7 @@ int brcmf_debug_create_memdump(struct brcmf_bus *bus, const void *data,
return err;
}

- dev_coredumpv(bus->dev, dump, len + ramsize, GFP_KERNEL);
+ dev_coredumpv(bus->dev, dump, len + ramsize);

return 0;
}
diff --git a/drivers/net/wireless/marvell/mwifiex/main.c b/drivers/net/wireless/marvell/mwifiex/main.c
index ace7371c477..26fef0ab1b0 100644
--- a/drivers/net/wireless/marvell/mwifiex/main.c
+++ b/drivers/net/wireless/marvell/mwifiex/main.c
@@ -1115,8 +1115,7 @@ void mwifiex_upload_device_dump(struct mwifiex_adapter *adapter)
*/
mwifiex_dbg(adapter, MSG,
"== mwifiex dump information to /sys/class/devcoredump start\n");
- dev_coredumpv(adapter->dev, adapter->devdump_data, adapter->devdump_len,
- GFP_KERNEL);
+ dev_coredumpv(adapter->dev, adapter->devdump_data, adapter->devdump_len);
mwifiex_dbg(adapter, MSG,
"== mwifiex dump information to /sys/class/devcoredump end\n");

diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
index bd687f7de62..5336fe8c668 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
@@ -2421,6 +2421,5 @@ void mt7615_coredump_work(struct work_struct *work)

dev_kfree_skb(skb);
}
- dev_coredumpv(dev->mt76.dev, dump, MT76_CONNAC_COREDUMP_SZ,
- GFP_KERNEL);
+ dev_coredumpv(dev->mt76.dev, dump, MT76_CONNAC_COREDUMP_SZ);
}
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
index a630ddbf19e..cac284f95ce 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
@@ -1630,8 +1630,7 @@ void mt7921_coredump_work(struct work_struct *work)
}

if (dump)
- dev_coredumpv(dev->mt76.dev, dump, MT76_CONNAC_COREDUMP_SZ,
- GFP_KERNEL);
+ dev_coredumpv(dev->mt76.dev, dump, MT76_CONNAC_COREDUMP_SZ);

mt7921_reset(&dev->mt76);
}
diff --git a/drivers/net/wireless/realtek/rtw88/main.c b/drivers/net/wireless/realtek/rtw88/main.c
index efabd5b1bf5..a276544cecd 100644
--- a/drivers/net/wireless/realtek/rtw88/main.c
+++ b/drivers/net/wireless/realtek/rtw88/main.c
@@ -414,7 +414,7 @@ static void rtw_fwcd_dump(struct rtw_dev *rtwdev)
* framework. Note that a new dump will be discarded if a previous one
* hasn't been released yet.
*/
- dev_coredumpv(rtwdev->dev, desc->data, desc->size, GFP_KERNEL);
+ dev_coredumpv(rtwdev->dev, desc->data, desc->size);
}

static void rtw_fwcd_free(struct rtw_dev *rtwdev, bool free_self)
diff --git a/drivers/net/wireless/realtek/rtw89/ser.c b/drivers/net/wireless/realtek/rtw89/ser.c
index 9e95ed97271..d28fe01ad72 100644
--- a/drivers/net/wireless/realtek/rtw89/ser.c
+++ b/drivers/net/wireless/realtek/rtw89/ser.c
@@ -127,7 +127,7 @@ static void rtw89_ser_cd_send(struct rtw89_dev *rtwdev,
* will be discarded if a previous one hasn't been released by
* framework yet.
*/
- dev_coredumpv(rtwdev->dev, buf, sizeof(*buf), GFP_KERNEL);
+ dev_coredumpv(rtwdev->dev, buf, sizeof(*buf));
}

static void rtw89_ser_cd_free(struct rtw89_dev *rtwdev,
diff --git a/drivers/remoteproc/qcom_q6v5_mss.c b/drivers/remoteproc/qcom_q6v5_mss.c
index af217de75e4..813d87faef6 100644
--- a/drivers/remoteproc/qcom_q6v5_mss.c
+++ b/drivers/remoteproc/qcom_q6v5_mss.c
@@ -597,7 +597,7 @@ static void q6v5_dump_mba_logs(struct q6v5 *qproc)
data = vmalloc(MBA_LOG_SIZE);
if (data) {
memcpy(data, mba_region, MBA_LOG_SIZE);
- dev_coredumpv(&rproc->dev, data, MBA_LOG_SIZE, GFP_KERNEL);
+ dev_coredumpv(&rproc->dev, data, MBA_LOG_SIZE);
}
memunmap(mba_region);
}
diff --git a/drivers/remoteproc/remoteproc_coredump.c b/drivers/remoteproc/remoteproc_coredump.c
index 4b093420d98..36ba7b300d5 100644
--- a/drivers/remoteproc/remoteproc_coredump.c
+++ b/drivers/remoteproc/remoteproc_coredump.c
@@ -309,7 +309,7 @@ void rproc_coredump(struct rproc *rproc)
phdr += elf_size_of_phdr(class);
}
if (dump_conf == RPROC_COREDUMP_ENABLED) {
- dev_coredumpv(&rproc->dev, data, data_size, GFP_KERNEL);
+ dev_coredumpv(&rproc->dev, data, data_size);
return;
}

@@ -449,7 +449,7 @@ void rproc_coredump_using_sections(struct rproc *rproc)
}

if (dump_conf == RPROC_COREDUMP_ENABLED) {
- dev_coredumpv(&rproc->dev, data, data_size, GFP_KERNEL);
+ dev_coredumpv(&rproc->dev, data, data_size);
return;
}

diff --git a/include/linux/devcoredump.h b/include/linux/devcoredump.h
index c008169ed2c..a9fba5e7046 100644
--- a/include/linux/devcoredump.h
+++ b/include/linux/devcoredump.h
@@ -52,8 +52,7 @@ static inline void _devcd_free_sgtable(struct scatterlist *table)


#ifdef CONFIG_DEV_COREDUMP
-void dev_coredumpv(struct device *dev, void *data, size_t datalen,
- gfp_t gfp);
+void dev_coredumpv(struct device *dev, void *data, size_t datalen);

void dev_coredumpm(struct device *dev, struct module *owner,
void *data, size_t datalen, gfp_t gfp,
@@ -65,7 +64,7 @@ void dev_coredumpsg(struct device *dev, struct scatterlist *table,
size_t datalen, gfp_t gfp);
#else
static inline void dev_coredumpv(struct device *dev, void *data,
- size_t datalen, gfp_t gfp)
+ size_t datalen)
{
vfree(data);
}
diff --git a/sound/soc/intel/catpt/dsp.c b/sound/soc/intel/catpt/dsp.c
index 346bec00030..d2afe9ff1e3 100644
--- a/sound/soc/intel/catpt/dsp.c
+++ b/sound/soc/intel/catpt/dsp.c
@@ -539,7 +539,7 @@ int catpt_coredump(struct catpt_dev *cdev)
pos += CATPT_DMA_REGS_SIZE;
}

- dev_coredumpv(cdev->dev, dump, dump_size, GFP_KERNEL);
+ dev_coredumpv(cdev->dev, dump, dump_size);

return 0;
}
--
2.17.1


2022-06-03 15:02:14

by Duoming Zhou

[permalink] [raw]
Subject: Re: [PATCH v4 1/2] devcoredump: remove the useless gfp_t parameter in dev_coredumpv

Hello,

On Thu, 2 Jun 2022 13:32:48 -0700 Jeff Johnson wrote:

> On 6/2/2022 6:33 AM, Duoming Zhou wrote:
> > The dev_coredumpv() could not be used in atomic context, because
> > it calls kvasprintf_const() and kstrdup() with GFP_KERNEL parameter.
> > The process is shown below:
> >
> > dev_coredumpv(..., gfp_t gfp)
> > dev_coredumpm
> > dev_set_name
> > kobject_set_name_vargs
> > kvasprintf_const(GFP_KERNEL, ...); //may sleep
> > kstrdup(s, GFP_KERNEL); //may sleep
> >
> > This patch removes gfp_t parameter of dev_coredumpv() and changes the
> > gfp_t parameter of dev_coredumpm() to GFP_KERNEL in order to show
> > dev_coredumpv() could not be used in atomic context.
>
> shouldn't you remove the gfp parameter to dev_coredumpm() as well since
> it is actually within that function where dev_set_name() is called which
> cannot be done in atomic context?

Thanks for your suggestion, I will remove the gfp_t parameter of dev_coredumpm() as well.

Best regards,
Duoming Zhou