The quilt patch titled
Subject: RDMA/umem: remove FOLL_FORCE usage
has been removed from the -mm tree. Its filename was
rdma-umem-remove-foll_force-usage.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: David Hildenbrand <david@xxxxxxxxxx>
Subject: RDMA/umem: remove FOLL_FORCE usage
Date: Wed, 16 Nov 2022 11:26:49 +0100
GUP now supports reliable R/O long-term pinning in COW mappings, such
that we break COW early. MAP_SHARED VMAs only use the shared zeropage so
far in one corner case (DAXFS file with holes), which can be ignored
because GUP does not support long-term pinning in fsdax (see
check_vma_flags()).
Consequently, FOLL_FORCE | FOLL_WRITE | FOLL_LONGTERM is no longer required
for reliable R/O long-term pinning: FOLL_LONGTERM is sufficient. So stop
using FOLL_FORCE, which is really only for ptrace access.
Link: https://lkml.kernel.org/r/20221116102659.70287-11-david@xxxxxxxxxx
Tested-by: Leon Romanovsky <leonro@xxxxxxxxxx> [over mlx4 and mlx5]
Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Cc: Leon Romanovsky <leon@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/core/umem.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/drivers/infiniband/core/umem.c~rdma-umem-remove-foll_force-usage
+++ a/drivers/infiniband/core/umem.c
@@ -156,7 +156,7 @@ struct ib_umem *ib_umem_get(struct ib_de
struct mm_struct *mm;
unsigned long npages;
int pinned, ret;
- unsigned int gup_flags = FOLL_WRITE;
+ unsigned int gup_flags = FOLL_LONGTERM;
/*
* If the combination of the addr and size requested for this memory
@@ -210,8 +210,8 @@ struct ib_umem *ib_umem_get(struct ib_de
cur_base = addr & PAGE_MASK;
- if (!umem->writable)
- gup_flags |= FOLL_FORCE;
+ if (umem->writable)
+ gup_flags |= FOLL_WRITE;
while (npages) {
cond_resched();
@@ -219,7 +219,7 @@ struct ib_umem *ib_umem_get(struct ib_de
min_t(unsigned long, npages,
PAGE_SIZE /
sizeof(struct page *)),
- gup_flags | FOLL_LONGTERM, page_list);
+ gup_flags, page_list);
if (pinned < 0) {
ret = pinned;
goto umem_release;
_
Patches currently in -mm which might be from david@xxxxxxxxxx are
selftests-vm-add-ksm-unmerge-tests.patch
mm-pagewalk-dont-trigger-test_walk-in-walk_page_vma.patch
selftests-vm-add-test-to-measure-madv_unmergeable-performance.patch
mm-ksm-simplify-break_ksm-to-not-rely-on-vm_fault_write.patch
mm-remove-vm_fault_write.patch
mm-ksm-fix-ksm-cow-breaking-with-userfaultfd-wp-via-fault_flag_unshare.patch
mm-pagewalk-add-walk_page_range_vma.patch
mm-ksm-convert-break_ksm-to-use-walk_page_range_vma.patch
mm-gup-remove-foll_migration.patch
