powerpc fixes for 6.9 #4

 - Fix incorrect delay handling in the plpks (keystore) code.

 - Fix a panic when an LPAR boots with a frozen PE.

Thanks to: Andrew Donnellan, Gaurav Batra, Nageswara R Sastry, Nayna Jain.
powerpc/pseries/iommu: LPAR panics during boot up with a frozen PE

At the time of LPAR boot up, partition firmware provides Open Firmware
property ibm,dma-window for the PE. This property is provided on the PCI
bus the PE is attached to.

There are execptions where the partition firmware might not provide this
property for the PE at the time of LPAR boot up. One of the scenario is
where the firmware has frozen the PE due to some error condition. This
PE is frozen for 24 hours or unless the whole system is reinitialized.

Within this time frame, if the LPAR is booted, the frozen PE will be
presented to the LPAR but ibm,dma-window property could be missing.

Today, under these circumstances, the LPAR oopses with NULL pointer
dereference, when configuring the PCI bus the PE is attached to.

  BUG: Kernel NULL pointer dereference on read at 0x000000c8
  Faulting instruction address: 0xc0000000001024c0
  Oops: Kernel access of bad area, sig: 7 [#1]
  LE PAGE_SIZE=64K MMU=Radix SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in:
  Supported: Yes
  CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.4.0-150600.9-default #1
  Hardware name: IBM,9043-MRX POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1060.00 (NM1060_023) hv:phyp pSeries
  NIP:  c0000000001024c0 LR: c0000000001024b0 CTR: c000000000102450
  REGS: c0000000037db5c0 TRAP: 0300   Not tainted  (6.4.0-150600.9-default)
  MSR:  8000000002009033 <SF,VEC,EE,ME,IR,DR,RI,LE>  CR: 28000822  XER: 00000000
  CFAR: c00000000010254c DAR: 00000000000000c8 DSISR: 00080000 IRQMASK: 0
  NIP [c0000000001024c0] pci_dma_bus_setup_pSeriesLP+0x70/0x2a0
  LR [c0000000001024b0] pci_dma_bus_setup_pSeriesLP+0x60/0x2a0
  Call Trace:
    pci_dma_bus_setup_pSeriesLP+0x60/0x2a0 (unreliable)

Fixes: b1fc44eaa9ba ("pseries/iommu/ddw: Fix kdump to work in absence of ibm,dma-window")
Signed-off-by: Gaurav Batra <gbatra@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240422205141.10662-1-gbatra@linux.ibm.com
1 file changed