s390 updates for 5.7-rc7

- Add missing R_390_JMP_SLOT relocation type in KASLR code.

- Fix set_huge_pte_at for empty ptes issue which has been uncovered with
  arch page table helper tests.

- Correct initrd location for kdump kernel.

- Fix s390_mmio_read/write with MIO in PCI code.
s390/kaslr: add support for R_390_JMP_SLOT relocation type

With certain kernel configurations, the R_390_JMP_SLOT relocation type
might be generated, which is not expected by the KASLR relocation code,
and the kernel stops with the message "Unknown relocation type".

This was found with a zfcpdump kernel config, where CONFIG_MODULES=n
and CONFIG_VFIO=n. In that case, symbol_get() is used on undefined
__weak symbols in virt/kvm/vfio.c, which results in the generation
of R_390_JMP_SLOT relocation types.

Fix this by handling R_390_JMP_SLOT similar to R_390_GLOB_DAT.

Fixes: 805bc0bc238f ("s390/kernel: build a relocatable kernel")
Cc: <stable@vger.kernel.org> # v5.2+
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
1 file changed