On Tue, Nov 12, 2019 at 08:27:10PM -0800, John Hubbard wrote:
Now that all other kernel callers of get_user_pages(FOLL_LONGTERM) have been converted to pin_longterm_pages(), lock it down:
Add an assertion to get_user_pages(), preventing callers from passing FOLL_LONGTERM (in addition to the existing assertion that prevents FOLL_PIN).
Remove the associated GUP_LONGTERM_BENCHMARK test.
Signed-off-by: John Hubbard jhubbard@nvidia.com
mm/gup.c | 8 ++++---- mm/gup_benchmark.c | 9 +-------- tools/testing/selftests/vm/gup_benchmark.c | 7 ++----- 3 files changed, 7 insertions(+), 17 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c index 82e7e4ce5027..90f5f95ee7ac 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1756,11 +1756,11 @@ long get_user_pages(unsigned long start, unsigned long nr_pages, struct vm_area_struct **vmas) { /*
* FOLL_PIN must only be set internally by the pin_user_page*() and* pin_longterm_*() APIs, never directly by the caller, so enforce that* with an assertion:
* FOLL_PIN and FOLL_LONGTERM must only be set internally by the* pin_user_page*() and pin_longterm_*() APIs, never directly by the* caller, so enforce that with an assertion:
- if (WARN_ON_ONCE(gup_flags & FOLL_PIN))
- if (WARN_ON_ONCE(gup_flags & (FOLL_PIN | FOLL_LONGTERM)))
Don't we want to block FOLL_LONGTERM in get_user_pages_fast() as well after all this?
Ira
return -EINVAL;return __gup_longterm_locked(current, current->mm, start, nr_pages, diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c index 8f980d91dbf5..679f0e6a0adb 100644 --- a/mm/gup_benchmark.c +++ b/mm/gup_benchmark.c @@ -6,7 +6,7 @@ #include <linux/debugfs.h> #define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) -#define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark) +/* Command 2 has been deleted. */ #define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark) #define PIN_FAST_BENCHMARK _IOWR('g', 4, struct gup_benchmark) #define PIN_LONGTERM_BENCHMARK _IOWR('g', 5, struct gup_benchmark) @@ -28,7 +28,6 @@ static void put_back_pages(int cmd, struct page **pages, unsigned long nr_pages) switch (cmd) { case GUP_FAST_BENCHMARK:
- case GUP_LONGTERM_BENCHMARK: case GUP_BENCHMARK: for (i = 0; i < nr_pages; i++) put_page(pages[i]);
@@ -97,11 +96,6 @@ static int __gup_benchmark_ioctl(unsigned int cmd, nr = get_user_pages_fast(addr, nr, gup->flags, pages + i); break;
case GUP_LONGTERM_BENCHMARK:nr = get_user_pages(addr, nr,gup->flags | FOLL_LONGTERM,pages + i, NULL);break;@@ -159,7 +153,6 @@ static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd, switch (cmd) { case GUP_FAST_BENCHMARK:
- case GUP_LONGTERM_BENCHMARK: case GUP_BENCHMARK: case PIN_FAST_BENCHMARK: case PIN_LONGTERM_BENCHMARK:
diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c index 03928e47a86f..836b7082db13 100644 --- a/tools/testing/selftests/vm/gup_benchmark.c +++ b/tools/testing/selftests/vm/gup_benchmark.c @@ -15,7 +15,7 @@ #define PAGE_SIZE sysconf(_SC_PAGESIZE) #define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) -#define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark) +/* Command 2 has been deleted. */ #define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark) /* @@ -49,7 +49,7 @@ int main(int argc, char **argv) char *file = "/dev/zero"; char *p;
- while ((opt = getopt(argc, argv, "m:r:n:f:abctTLUuwSH")) != -1) {
- while ((opt = getopt(argc, argv, "m:r:n:f:abctTUuwSH")) != -1) { switch (opt) { case 'a': cmd = PIN_FAST_BENCHMARK;
@@ -75,9 +75,6 @@ int main(int argc, char **argv) case 'T': thp = 0; break;
case 'L':cmd = GUP_LONGTERM_BENCHMARK;break;-- 2.24.0