mirror of
https://github.com/torvalds/linux.git
synced 2024-12-03 01:21:28 +00:00
45b21cfeb2
Recently we merged the native xive support for Power9, and then separately some
reworks for doorbell IPI support. In isolation both series were OK, but the
merged result had a bug in one case.
On P9 DD1 we use pnv_p9_dd1_cause_ipi() which tries to use doorbells, and then
falls back to the interrupt controller. However the fallback is implemented by
calling icp_ops->cause_ipi. But now that xive support is merged we might be
using xive, in which case icp_ops is not initialised, it's a xics specific
structure. This leads to an oops such as:
Unable to handle kernel paging request for data at address 0x00000028
Oops: Kernel access of bad area, sig: 11 [#1]
NIP pnv_p9_dd1_cause_ipi+0x74/0xe0
LR smp_muxed_ipi_message_pass+0x54/0x70
To fix it, rather than using icp_ops which might be NULL, have both xics and
xive set smp_ops->cause_ipi, and then in the powernv code we save that as
ic_cause_ipi before overriding smp_ops->cause_ipi. For paranoia add a WARN_ON()
to check if somehow smp_ops->cause_ipi is NULL.
Fixes:
|
||
|---|---|---|
| .. | ||
| 8xx | ||
| 40x | ||
| 44x | ||
| 52xx | ||
| 82xx | ||
| 83xx | ||
| 85xx | ||
| 86xx | ||
| 512x | ||
| amigaone | ||
| cell | ||
| chrp | ||
| embedded6xx | ||
| maple | ||
| pasemi | ||
| powermac | ||
| powernv | ||
| ps3 | ||
| pseries | ||
| fsl_uli1575.c | ||
| Kconfig | ||
| Kconfig.cputype | ||
| Makefile | ||