Commit
49f86ec21c01 ("rtlwifi: Change long delays to sleeps") was correct
for most cases; however, driver rtl8192ce calls the affected routines while
in atomic context. The kernel bug output is as follows:
BUG: scheduling while atomic: wpa_supplicant/627/0x00000002
[...]
[<
ffffffff815c2b39>] __schedule+0x899/0xad0
[<
ffffffff815c2dac>] schedule+0x3c/0x90
[<
ffffffff815c5bb2>] schedule_hrtimeout_range_clock+0xa2/0x120
[<
ffffffff810e8b80>] ? hrtimer_init+0x120/0x120
[<
ffffffff815c5ba6>] ? schedule_hrtimeout_range_clock+0x96/0x120
[<
ffffffff815c5c43>] schedule_hrtimeout_range+0x13/0x20
[<
ffffffff815c568f>] usleep_range+0x4f/0x70
[<
ffffffffa0667218>] rtl_rfreg_delay+0x38/0x50 [rtlwifi]
[<
ffffffffa06dd0e7>] rtl92c_phy_config_rf_with_headerfile+0xc7/0xe0 [rtl8192ce]
To fix this bug, three of the changes from delay to sleep are reverted.
Unfortunately, one of the changes involves a delay of 50 msec. The calling
code will be modified so that this long delay can be avoided; however,
this change is being pushed now to fix the problem in kernel 4.6.0.
Fixes: 49f86ec21c01 ("rtlwifi: Change long delays to sleeps")
Reported-by: James Feeney <james@nurealm.net>
Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: James Feeney <james@nurealm.net>
Cc: Stable <stable@vger.kernel.org> [4.6+]
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
void rtl_addr_delay(u32 addr)
{
if (addr == 0xfe)
- msleep(50);
+ mdelay(50);
else if (addr == 0xfd)
msleep(5);
else if (addr == 0xfc)
rtl_addr_delay(addr);
} else {
rtl_set_rfreg(hw, rfpath, addr, mask, data);
- usleep_range(1, 2);
+ udelay(1);
}
}
EXPORT_SYMBOL(rtl_rfreg_delay);
rtl_addr_delay(addr);
} else {
rtl_set_bbreg(hw, addr, MASKDWORD, data);
- usleep_range(1, 2);
+ udelay(1);
}
}
EXPORT_SYMBOL(rtl_bb_delay);