Boot panic on Lenovo P50s since r367998

[Yuri Pankov]

Marc Veldman wrote:
> Hello,
> 
> since r367998 my Lenovo P50s panics on boot:
> 
> mmc0: detached
> panic: Bad link elm 0xfffff80003a73300 next->prep != elm
> cupid=3
> time=2
> KDB: stack backtrace:
> db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 0xffffffff8299a9c0
> vpanic() at vpanic+0x181/frame 0xffffffff8299aa10
> panic() at panic+0x43/frame 0xffffffff8299aa70
> config_intrhook_disestablish() at config_intrhook_disestablish+0xf3/frame 0xffffffff8299aa90
> config_intrhook_oneshot_func() at config_intrhook_oneshot_func+0x18/frame 0xffffffff8299aab0
> run_interrupt_driven_config_hooks() at run_interrupt_driven_config_hooks+0x77/frame 0xffffffff8299aad0
> boot_run_interrupt_driven_config_hooks() at boot_run_interrupt_driven_config_hooks+0x1f/frame 0xffffffff8299ab60
> mi_startup() at mi_startup+0xec/frame 0xffffffff8299abb0
> btext() at btext+0x2c
> KDB: enter: panic
> [thread pid 0 tid 100000]
> Stopped at     kdb_enter+0x37: movq     $0,0x10ada46(%rip)

r367998 adds rtsx driver for card reader, seems to work for me on P51 
(as in "detected and does not panic", I don't have any cards around to 
really test it):

rtsx0 at pci0:63:0:0:	class=0xff0000 rev=0x01 hdr=0x00 vendor=0x10ec 
device=0x525a subvendor=0x17aa subdevice=0x224d
     vendor	= 'Realtek Semiconductor Co., Ltd.'
     device	= 'RTS525A PCI Express Card Reader'

To confirm the issue is indeed in rtsx, does disabling the card reader 
in bios help?  If it does, what is the device exactly (`pciconf -lv` 
when booted on pre-r367998)?