linux_dsm_epyc7002/arch
Christophe Leroy 542db12a9c powerpc: Fix random segfault when freeing hugetlb range
The following random segfault is observed from time to time with
map_hugetlb selftest:

root@localhost:~# ./map_hugetlb 1 19
524288 kB hugepages
Mapping 1 Mbytes
Segmentation fault

[   31.219972] map_hugetlb[365]: segfault (11) at 117 nip 77974f8c lr 779a6834 code 1 in ld-2.23.so[77966000+21000]
[   31.220192] map_hugetlb[365]: code: 9421ffc0 480318d1 93410028 90010044 9361002c 93810030 93a10034 93c10038
[   31.220307] map_hugetlb[365]: code: 93e1003c 93210024 8123007c 81430038 <80e90004> 814a0004 7f443a14 813a0004
[   31.221911] BUG: Bad rss-counter state mm:(ptrval) type:MM_FILEPAGES val:33
[   31.229362] BUG: Bad rss-counter state mm:(ptrval) type:MM_ANONPAGES val:5

This fault is due to hugetlb_free_pgd_range() freeing page tables
that are also used by regular pages.

As explain in the comment at the beginning of
hugetlb_free_pgd_range(), the verification done in free_pgd_range()
on floor and ceiling is not done here, which means
hugetlb_free_pte_range() can free outside the expected range.

As the verification cannot be done in hugetlb_free_pgd_range(), it
must be done in hugetlb_free_pte_range().

Fixes: b250c8c08c ("powerpc/8xx: Manage 512k huge pages as standard pages.")
Cc: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/f0cb2a5477cd87d1eaadb128042e20aeb2bc2859.1598860677.git.christophe.leroy@csgroup.eu
2020-09-15 22:13:30 +10:00
..
alpha iomap: constify ioreadX() iomem argument (as in generic implementation) 2020-08-14 19:56:57 -07:00
arc mm/gup: remove task_struct pointer for all gup code 2020-08-12 10:58:04 -07:00
arm all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
arm64 - Allow booting of late secondary CPUs affected by erratum 1418040 2020-08-22 10:17:36 -07:00
c6x Merge branch 'work.regset' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2020-08-07 09:29:25 -07:00
csky mm/csky: use general page fault accounting 2020-08-12 10:58:03 -07:00
h8300 uaccess: remove segment_eq 2020-08-12 10:57:58 -07:00
hexagon mm/hexagon: use general page fault accounting 2020-08-12 10:58:03 -07:00
ia64 arch/ia64: Restore arch-specific pgd_offset_k implementation 2020-08-17 21:50:54 +03:00
m68k Cleanup, SECCOMP_FILTER support, message printing fixes, and other 2020-08-15 18:50:32 -07:00
microblaze all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
mips * PAE and PKU bugfixes for x86 2020-08-22 10:03:05 -07:00
nds32 mm/nds32: use general page fault accounting 2020-08-12 10:58:03 -07:00
nios2 mm/nios2: use general page fault accounting 2020-08-12 10:58:03 -07:00
openrisc OpenRISC updates for 5.9 2020-08-14 14:04:53 -07:00
parisc parisc: fix PMD pages allocation by restoring pmd_alloc_one() 2020-08-16 10:53:13 -07:00
powerpc powerpc: Fix random segfault when freeing hugetlb range 2020-09-15 22:13:30 +10:00
riscv riscv: Add SiFive drivers to rv32_defconfig 2020-08-20 11:00:21 -07:00
s390 s390/pci: fix PF/VF linking on hot plug 2020-08-17 13:17:34 +02:00
sh Cleanup, SECCOMP_FILTER support, message printing fixes, and other 2020-08-15 18:50:32 -07:00
sparc all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
um Cleanup, SECCOMP_FILTER support, message printing fixes, and other 2020-08-15 18:50:32 -07:00
x86 A single fix for x86 which removes the RDPID usage from the paranoid entry 2020-08-23 11:21:16 -07:00
xtensa all arch: remove system call sys_sysctl 2020-08-14 19:56:56 -07:00
.gitignore
Kconfig A set oftimekeeping/VDSO updates: 2020-08-14 14:26:08 -07:00