From: Vasily Gorbik <g...@linux.ibm.com> [ Upstream commit 5bedf8aa03c28cb8dc98bdd32a41b66d8f7d3eaa ]
Since proc_dointvec does not perform value range control, proc_dointvec_minmax should be used to limit value range, which is clearly intended here, as the internal representation of the value: unsigned int alloc_pgste:1; In fact it currently works, since we have mm->context.alloc_pgste = page_table_allocate_pgste || ... ... since commit 23fefe119ceb5 ("s390/kvm: avoid global config of vm.alloc_pgste=1") Before that it was mm->context.alloc_pgste = page_table_allocate_pgste; which was broken. That was introduced with commit 0b46e0a3ec0d7 ("s390/kvm: remove delayed reallocation of page tables for KVM"). Fixes: 0b46e0a3ec0d7 ("s390/kvm: remove delayed reallocation of page tables for KVM") Acked-by: Christian Borntraeger <borntrae...@de.ibm.com> Reviewed-by: Heiko Carstens <heiko.carst...@de.ibm.com> Signed-off-by: Vasily Gorbik <g...@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidef...@de.ibm.com> Signed-off-by: Sasha Levin <alexander.le...@microsoft.com> --- arch/s390/mm/pgalloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/s390/mm/pgalloc.c b/arch/s390/mm/pgalloc.c index 995f78532cc2..781a044e1702 100644 --- a/arch/s390/mm/pgalloc.c +++ b/arch/s390/mm/pgalloc.c @@ -26,7 +26,7 @@ static struct ctl_table page_table_sysctl[] = { .data = &page_table_allocate_pgste, .maxlen = sizeof(int), .mode = S_IRUGO | S_IWUSR, - .proc_handler = proc_dointvec, + .proc_handler = proc_dointvec_minmax, .extra1 = &page_table_allocate_pgste_min, .extra2 = &page_table_allocate_pgste_max, }, -- 2.17.1