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wifi: rtlwifi: rtl8723be: Remove unnecessary irq save/restore in hw_init()

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rtl8723be hw_init() calls local_save_flags(flags) followed by
local_irq_enable(). Later, local_irq_restore(flags) is called.

This causes warnings from Lockdep on boot and modprobe,
as local_irq_restore(flags) should only be called while irqs are disabled.
The warning was introduced to detect this class of bug in [1].

With testing I found that all paths which call hw_init() have irqs
already enabled for rtl8723be.

Furthermore, the calls were originally added for the rtl8192ce
in commit f78bccd79b ("rtlwifi: rtl8192ce: Fix too long disable of IRQs")
before later being added to most other rtlwifi drivers.

Commit d3feae41a3 ("rtlwifi: Update power-save routines for 062814 driver")
then replaces the call to spin_lock_irqsave() before hw_init(),
and thus the codepath which caused irqs to be disabled in hw_init and
prompted the original commit has been removed.

The same irq save/restore pattern is also present in the hw_init() of
rtl8192ce, rtl8723ae, rtl8188ee, rtl8192se and rtl8192cu,
however I don't have the hardware to test them,
so I did not include them in my changes.

Tested on a Razer Blade 14 2017.

Example of output from Lockdep prior to fix:

raw_local_irq_restore() called with IRQs enabled

...

Call Trace:
<TASK>
rtl8723be_hw_init+0x5992/0x7220 [rtl8723be]
? static_obj+0x61/0xa0
rtl_pci_start+0x222/0x5c0 [rtl_pci]
rtl_op_start+0x128/0x1a0 [rtlwifi]
? __kasan_check_read+0x11/0x20
drv_start+0x16c/0x550 [mac80211]

...

irq event stamp: 887679
hardirqs last  enabled at (887689): [<ffffffff96511170>] __up_console_sem+0x90/0xa0
hardirqs last disabled at (887698): [<ffffffff96511155>] __up_console_sem+0x75/0xa0
softirqs last  enabled at (887670): [<ffffffff962f4675>] __irq_exit_rcu+0x175/0x2f0
softirqs last disabled at (887649): [<ffffffff962f4675>] __irq_exit_rcu+0x175/0x2f0
---[ end trace 0000000000000000 ]---

[1] https://lore.kernel.org/all/20210111153707.10071-1-mark.rutland@arm.com/

Signed-off-by: William Hansen-Baird <william.hansen.baird@gmail.com>
Acked-by: Ping-Ke Shih <pkshih@realtek.com>
Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
Link: https://patch.msgid.link/20260609095359.2964193-1-william.hansen.baird@gmail.com
This commit is contained in:
William Hansen-Baird 2026-06-09 11:53:59 +02:00 • committed by Ping-Ke Shih
commit 1b4cd55626
1 changed files with 0 additions and 6 deletions
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