Regression found on arm gcc-11 builds with tinyconfig and allnoconfig.
Following build warnings / errors reported on stable-rc 4.9.
metadata:
git_describe: v4.9.290-208-gb2ae18f41670
git_repo: https://gitlab.com/Linaro/lkft/mirrors/stable/linux-stable-rc
git_short_log: b2ae18f41670 (\"Linux 4.9.291-rc1\")
target_arch: arm
toolchain: gcc-11 / gcc-10 / gcc-9 / gcc-8
build error :
--------------
make --silent --keep-going --jobs=8
O=/home/tuxbuild/.cache/tuxmake/builds/current ARCH=arm
CROSS_COMPILE=arm-linux-gnueabihf- 'CC=sccache
arm-linux-gnueabihf-gcc' 'HOSTCC=sccache gcc'
In file included from arch/arm/include/asm/tlb.h:28,
from arch/arm/mm/init.c:34:
include/asm-generic/tlb.h: In function 'tlb_flush_pmd_range':
include/asm-generic/tlb.h:208:54: error: 'PMD_SIZE' undeclared (first
use in this function); did you mean 'PUD_SIZE'?
208 | if (tlb->page_size != 0 && tlb->page_size != PMD_SIZE)
| ^~~~~~~~
| PUD_SIZE
include/asm-generic/tlb.h:208:54: note: each undeclared identifier is
reported only once for each function it appears in
make[2]: *** [scripts/Makefile.build:307: arch/arm/mm/init.o] Error 1
make[2]: Target '__build' not remade because of errors.
make[1]: *** [Makefile:1036: arch/arm/mm] Error 2
Reported-by: Linux Kernel Functional Testing <lkft@xxxxxxxxxx>
Patch pointing to,
hugetlbfs: flush TLBs correctly after huge_pmd_unshare
commit a4a118f2eead1d6c49e00765de89878288d4b890 upstream.
When __unmap_hugepage_range() calls to huge_pmd_unshare() succeed, a TLB
flush is missing. This TLB flush must be performed before releasing the
i_mmap_rwsem, in order to prevent an unshared PMDs page from being
released and reused before the TLB flush took place.
Arguably, a comprehensive solution would use mmu_gather interface to
batch the TLB flushes and the PMDs page release, however it is not an
easy solution: (1) try_to_unmap_one() and try_to_migrate_one() also call
huge_pmd_unshare() and they cannot use the mmu_gather interface; and (2)
deferring the release of the page reference for the PMDs page until
after i_mmap_rwsem is dropeed can confuse huge_pmd_unshare() into
thinking PMDs are shared when they are not.
Fix __unmap_hugepage_range() by adding the missing TLB flush, and
forcing a flush when unshare is successful.
Fixes: 24669e58477e ("hugetlb: use mmu_gather instead of a temporary
linked list for accumulating pages)" # 3.6
Signed-off-by: Nadav Amit <namit@xxxxxxxxxx>
Reviewed-by: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxxxxxxx>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
build link:
-----------
https://builds.tuxbuild.com//21Mf9eMMjq4oO5ZflMwRCPssSc0/build.log
build config:
-------------
https://builds.tuxbuild.com//21Mf9eMMjq4oO5ZflMwRCPssSc0/config
# To install tuxmake on your system globally
# sudo pip3 install -U tuxmake
tuxmake --runtime podman --target-arch arm --toolchain gcc-11
--kconfig tinyconfig
--
Linaro LKFT
https://lkft.linaro.org
