linux_dsm_epyc7002/arch/x86/mm
Qian Cai cb38f82043 x86/mm/pat: Mark an intentional data race
cpa_4k_install could be accessed concurrently as noticed by KCSAN,

read to 0xffffffffaa59a000 of 8 bytes by interrupt on cpu 7:
cpa_inc_4k_install arch/x86/mm/pat/set_memory.c:131 [inline]
__change_page_attr+0x10cf/0x1840 arch/x86/mm/pat/set_memory.c:1514
__change_page_attr_set_clr+0xce/0x490 arch/x86/mm/pat/set_memory.c:1636
__set_pages_np+0xc4/0xf0 arch/x86/mm/pat/set_memory.c:2148
__kernel_map_pages+0xb0/0xc8 arch/x86/mm/pat/set_memory.c:2178
kernel_map_pages include/linux/mm.h:2719 [inline] <snip>

write to 0xffffffffaa59a000 of 8 bytes by task 1 on cpu 6:
cpa_inc_4k_install arch/x86/mm/pat/set_memory.c:131 [inline]
__change_page_attr+0x10ea/0x1840 arch/x86/mm/pat/set_memory.c:1514
__change_page_attr_set_clr+0xce/0x490 arch/x86/mm/pat/set_memory.c:1636
__set_pages_p+0xc4/0xf0 arch/x86/mm/pat/set_memory.c:2129
__kernel_map_pages+0x2e/0xc8 arch/x86/mm/pat/set_memory.c:2176
kernel_map_pages include/linux/mm.h:2719 [inline] <snip>

Both accesses are due to the same "cpa_4k_install++" in
cpa_inc_4k_install. A data race here could be potentially undesirable:
depending on compiler optimizations or how x86 executes a non-LOCK'd
increment, it may lose increments, corrupt the counter, etc. Since this
counter only seems to be used for printing some stats, this data race
itself is unlikely to cause harm to the system though. Thus, mark this
intentional data race using the data_race() marco.

Suggested-by: Macro Elver <elver@google.com>
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29 12:04:47 -07:00
..
pat x86/mm/pat: Mark an intentional data race 2020-06-29 12:04:47 -07:00
amdtopology.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
cpu_entry_area.c x86/entry: Remove DBn stacks 2020-06-11 15:15:23 +02:00
debug_pagetables.c mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
dump_pagetables.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
extable.c x86/entry: Treat BUG/WARN as NMI-like entries 2020-06-12 12:12:57 +02:00
fault.c maccess: rename probe_kernel_address to get_kernel_nofault 2020-06-18 11:14:40 -07:00
highmem_32.c arch/kunmap_atomic: consolidate duplicate code 2020-06-04 19:06:22 -07:00
hugetlbpage.c hugetlbfs: remove hugetlb_add_hstate() warning for existing hstate 2020-06-03 20:09:46 -07:00
ident_map.c x86/mm: Stop pretending pgtable_l5_enabled is a variable 2018-05-19 11:56:57 +02:00
init_32.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
init_64.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
init.c x86/mm: simplify init_trampoline() and surrounding logic 2020-06-09 09:39:13 -07:00
iomap_32.c x86/mm/pat: Rename <asm/pat.h> => <asm/memtype.h> 2019-12-10 10:12:55 +01:00
ioremap.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
kasan_init_64.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
kaslr.c x86/mm: simplify init_trampoline() and surrounding logic 2020-06-09 09:39:13 -07:00
kmmio.c Misc changes: 2020-06-05 11:18:53 -07:00
maccess.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
Makefile Merge branch 'x86/kdump' into locking/kcsan, to resolve conflicts 2020-03-21 09:24:41 +01:00
mem_encrypt_boot.S mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
mem_encrypt_identity.c Merge branch 'x86-kdump-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-07-09 11:52:34 -07:00
mem_encrypt.c x86/tlb: Move __flush_tlb() out of line 2020-04-26 11:00:05 +02:00
mm_internal.h x86/mm: thread pgprot_t through init_memory_mapping() 2020-04-10 15:36:21 -07:00
mmap.c x86/mm/mmap: Fix -Wmissing-prototypes warnings 2020-04-22 20:19:48 +02:00
mmio-mod.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
numa_32.c x86/mm: Drop deprecated DISCONTIGMEM support for 32-bit 2020-05-28 18:34:30 +02:00
numa_64.c mm: remove include/linux/bootmem.h 2018-10-31 08:54:16 -07:00
numa_emulation.c x86/mm: Mark setup_emu2phys_nid() static 2020-03-27 11:07:30 +01:00
numa_internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
numa.c mm: rename free_area_init_node() to free_area_init_memoryless_node() 2020-06-03 20:09:44 -07:00
pf_in.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
pf_in.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156 2019-05-30 11:26:35 -07:00
pgtable_32.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
pgtable.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
physaddr.c mm, x86/mm: Untangle address space layout definitions from basic pgtable type definitions 2019-12-10 10:12:55 +01:00
physaddr.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pkeys.c mm/vma: introduce VM_ACCESS_FLAGS 2020-04-10 15:36:21 -07:00
pti.c x86/entry: Unbreak __irqentry_text_start/end magic 2020-06-11 15:15:29 +02:00
setup_nx.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
srat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
testmmiotrace.c remove ioremap_nocache and devm_ioremap_nocache 2020-01-06 09:45:59 +01:00
tlb.c Misc changes: 2020-06-05 11:18:53 -07:00