# git rev-parse -q --verify 2f763a4ece533902b68162890948ad5ecfbdc922^{commit}
2f763a4ece533902b68162890948ad5ecfbdc922
already have revision, skipping fetch
# git checkout -q -f -B kisskb 2f763a4ece533902b68162890948ad5ecfbdc922
# git clean -qxdf
# < git log -1
# commit 2f763a4ece533902b68162890948ad5ecfbdc922
# Author: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
# Date:   Wed Jul 10 15:20:18 2019 +1000
# 
#     powerpc: mm: Limit rma_size to 1TB when running without HV mode
#     
#     The virtual real mode addressing (VRMA) mechanism is used when a
#     partition is using HPT (Hash Page Table) translation and performs
#     real mode accesses (MSR[IR|DR] = 0) in non-hypervisor mode. In this
#     mode effective address bits 0:23 are treated as zero (i.e. the access
#     is aliased to 0) and the access is performed using an implicit 1TB SLB
#     entry.
#     
#     The size of the RMA (Real Memory Area) is communicated to the guest as
#     the size of the first memory region in the device tree. And because of
#     the mechanism described above can be expected to not exceed 1TB. In the
#     event that the host erroneously represents the RMA as being larger than
#     1TB, guest accesses in real mode to memory addresses above 1TB will be
#     aliased down to below 1TB. This means that a memory access performed in
#     real mode may differ to one performed in virtual mode for the same memory
#     address, which would likely have unintended consequences.
#     
#     To avoid this outcome have the guest explicitly limit the size of the
#     RMA to the current maximum, which is 1TB. This means that even if the
#     first memory block is larger than 1TB, only the first 1TB should be
#     accessed in real mode.
#     
#     Fixes: c3ab300ea555 ("powerpc: Add POWER9 cputable entry")
#     Cc: stable@vger.kernel.org # v4.6+
#     Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
#     Tested-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
#     Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
#     Link: https://lore.kernel.org/r/20190710052018.14628-1-sjitindarsingh@gmail.com
# < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc --version
# < /opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-ld --version
# < git log --format=%s --max-count=1 2f763a4ece533902b68162890948ad5ecfbdc922
# < make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_wii_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  wii_defconfig
# make -s -j 48 ARCH=powerpc O=/kisskb/build/powerpc-fixes_wii_defconfig_powerpc-gcc5 CROSS_COMPILE=/opt/cross/kisskb/korg/gcc-5.5.0-nolibc/powerpc64-linux/bin/powerpc64-linux-  
/kisskb/src/kernel/futex.c: In function 'do_futex':
/kisskb/src/kernel/futex.c:1645:17: warning: 'oldval' may be used uninitialized in this function [-Wmaybe-uninitialized]
   return oldval == cmparg;
                 ^
/kisskb/src/kernel/futex.c:1620:6: note: 'oldval' was declared here
  int oldval, ret;
      ^
INFO: Uncompressed kernel (size 0x90ac0c) overlaps the address of the wrapper(0x600000)
INFO: Fixing the link_address of wrapper to (0xa00000)
Completed OK
# rm -rf /kisskb/build/powerpc-fixes_wii_defconfig_powerpc-gcc5
# Build took: 0:00:55.747869