kernel_optimize_test/arch
Niklas Schnelle 80bfed369b s390/pci: move pseudo-MMIO to prevent MIO overlap
commit 52d04d408185b7aa47628d2339c28ec70074e0ae upstream.

When running without MIO support, with pci=nomio or for devices which
are not MIO-capable the zPCI subsystem generates pseudo-MMIO addresses
to allow access to PCI BARs via MMIO based Linux APIs even though the
platform uses function handles and BAR numbers.

This is done by stashing an index into our global IOMAP array which
contains the function handle in the 16 most significant bits of the
addresses returned by ioremap() always setting the most significant bit.

On the other hand the MIO addresses assigned by the platform for use,
while requiring special instructions, allow PCI access with virtually
mapped physical addresses. Now the problem is that these MIO addresses
and our own pseudo-MMIO addresses may overlap, while functionally this
would not be a problem by itself this overlap is detected by common code
as both address types are added as resources in the iomem_resource tree.
This leads to the overlapping resource claim of either the MIO capable
or non-MIO capable devices with being rejected.

Since PCI is tightly coupled to the use of the iomem_resource tree, see
for example the code for request_mem_region(), we can't reasonably get
rid of the overlap being detected by keeping our pseudo-MMIO addresses
out of the iomem_resource tree.

Instead let's move the range used by our own pseudo-MMIO addresses by
starting at (1UL << 62) and only using addresses below (1UL << 63) thus
avoiding the range currently used for MIO addresses.

Fixes: c7ff0e918a ("s390/pci: deal with devices that have no support for MIO instructions")
Cc: stable@vger.kernel.org # 5.3+
Reviewed-by: Pierre Morel <pmorel@linux.ibm.com>
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-12-08 09:03:21 +01:00
..
alpha
arc
arm ARM: socfpga: Fix crash with CONFIG_FORTIRY_SOURCE 2021-12-01 09:19:03 +01:00
arm64 arm64: vdso32: suppress error message for 'make mrproper' 2021-11-26 10:39:18 +01:00
c6x
csky
h8300
hexagon hexagon: clean up timer-regs.h 2021-11-26 10:39:19 +01:00
ia64
m68k m68k: set a default value for MEMORY_RESERVE 2021-11-18 14:04:24 +01:00
microblaze
mips MIPS: use 3-level pgtable for 64KB page size on MIPS_VA_BITS_48 2021-12-01 09:19:07 +01:00
nds32
nios2
openrisc openrisc: fix SMP tlb flush NULL pointer dereference 2021-11-18 14:04:25 +01:00
parisc Revert "parisc: Fix backtrace to always include init funtion names" 2021-12-01 09:19:00 +01:00
powerpc powerpc/pseries/ddw: Revert "Extend upper limit for huge DMA window for persistent memory" 2021-12-08 09:03:18 +01:00
riscv
s390 s390/pci: move pseudo-MMIO to prevent MIO overlap 2021-12-08 09:03:21 +01:00
sh sh: define __BIG_ENDIAN for math-emu 2021-11-26 10:39:12 +01:00
sparc
um
x86 x86/Kconfig: Fix an unused variable error in dell-smm-hwmon 2021-11-26 10:39:22 +01:00
xtensa
.gitignore
Kconfig arch/cc: Introduce a function to check for confidential computing features 2021-11-18 14:04:32 +01:00