linux/arch/s390
Alexander Egorenkov c2337a40e0 s390/kexec: fix ipl report address for kdump
This commit addresses the following erroneous situation with file-based
kdump executed on a system with a valid IPL report.

On s390, a kdump kernel, its initrd and IPL report if present are loaded
into a special and reserved on boot memory region - crashkernel. When
a system crashes and kdump was activated before, the purgatory code
is entered first which swaps the crashkernel and [0 - crashkernel size]
memory regions. Only after that the kdump kernel is entered. For this
reason, the pointer to an IPL report in lowcore must point to the IPL report
after the swap and not to the address of the IPL report that was located in
crashkernel memory region before the swap. Failing to do so, makes the
kdump's decompressor try to read memory from the crashkernel memory region
which already contains the production's kernel memory.

The situation described above caused spontaneous kdump failures/hangs
on systems where the Secure IPL is activated because on such systems
an IPL report is always present. In that case kdump's decompressor tried
to parse an IPL report which frequently lead to illegal memory accesses
because an IPL report contains addresses to various data.

Cc: <stable@vger.kernel.org>
Fixes: 99feaa717e ("s390/kexec_file: Create ipl report and pass to next kernel")
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-01-10 14:37:02 +01:00
..
appldata s390/appldata: remove power management callbacks 2022-12-02 18:25:04 +01:00
boot s390: fix -Wundef warning for CONFIG_KERNEL_ZSTD 2023-01-09 14:30:36 +01:00
configs random: use random.trust_{bootloader,cpu} command line option only 2022-11-18 02:18:10 +01:00
crypto crypto: Kconfig - simplify cipher entries 2022-08-26 18:50:43 +08:00
hypfs s390/hypfs: remove unused info_blk_hdr__pcpus() function 2022-11-23 16:24:07 +01:00
include s390/debug: add _ASM_S390_ prefix to header guard 2023-01-06 16:38:21 +01:00
kernel s390/kexec: fix ipl report address for kdump 2023-01-10 14:37:02 +01:00
kvm IOMMU Updates for Linux v6.2 2022-12-19 08:34:39 -06:00
lib s390/uaccess: add missing EX_TABLE entries to __clear_user() 2022-10-26 14:47:30 +02:00
mm ARM64: 2022-12-15 11:12:21 -08:00
net
pci IOMMU Updates for Linux v6.2 2022-12-19 08:34:39 -06:00
purgatory s390/purgatory: remove duplicated build rule of kexec-purgatory.o 2022-06-30 14:18:16 +02:00
tools KVM: s390: Add facility 197 to the allow list 2022-07-13 15:25:25 +02:00
Kbuild
Kconfig s390 updates for 6.2 merge window 2022-12-12 11:04:08 -08:00
Kconfig.debug s390/Kconfig.debug: fix indentation 2022-06-01 12:03:15 +02:00
Makefile s390: always build relocatable kernel 2022-11-08 19:32:32 +01:00