6.6-stable review patch. If anyone has any objections, please let me know.
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From: Lorenzo Stoakes lstoakes@gmail.com
[ Upstream commit 0f20bba1688bdf3b32df0162511a67d4eda15790 ]
Rather than open-coding a list of internal GUP flags in is_valid_gup_args(), define which ones are internal.
In addition, explicitly check to see if the user passed in FOLL_TOUCH somehow, as this appears to have been accidentally excluded.
Link: https://lkml.kernel.org/r/971e013dfe20915612ea8b704e801d7aef9a66b6.169628809... Signed-off-by: Lorenzo Stoakes lstoakes@gmail.com Reviewed-by: Arnd Bergmann arnd@arndb.de Reviewed-by: David Hildenbrand david@redhat.com Reviewed-by: Jason Gunthorpe jgg@nvidia.com Cc: Adrian Hunter adrian.hunter@intel.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Arnaldo Carvalho de Melo acme@kernel.org Cc: Catalin Marinas catalin.marinas@arm.com Cc: Ian Rogers irogers@google.com Cc: Ingo Molnar mingo@redhat.com Cc: Jiri Olsa jolsa@kernel.org Cc: John Hubbard jhubbard@nvidia.com Cc: Mark Rutland mark.rutland@arm.com Cc: Namhyung Kim namhyung@kernel.org Cc: Oleg Nesterov oleg@redhat.com Cc: Peter Zijlstra peterz@infradead.org Cc: Richard Cochran richardcochran@gmail.com Cc: Will Deacon will@kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Stable-dep-of: 631426ba1d45 ("mm/madvise: make MADV_POPULATE_(READ|WRITE) handle VM_FAULT_RETRY properly") Signed-off-by: Sasha Levin sashal@kernel.org --- mm/gup.c | 5 ++--- mm/internal.h | 3 +++ 2 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/mm/gup.c b/mm/gup.c index 2f8a2d89fde19..b21b33d1787e1 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -2227,12 +2227,11 @@ static bool is_valid_gup_args(struct page **pages, int *locked, /* * These flags not allowed to be specified externally to the gup * interfaces: - * - FOLL_PIN/FOLL_TRIED/FOLL_FAST_ONLY are internal only + * - FOLL_TOUCH/FOLL_PIN/FOLL_TRIED/FOLL_FAST_ONLY are internal only * - FOLL_REMOTE is internal only and used on follow_page() * - FOLL_UNLOCKABLE is internal only and used if locked is !NULL */ - if (WARN_ON_ONCE(gup_flags & (FOLL_PIN | FOLL_TRIED | FOLL_UNLOCKABLE | - FOLL_REMOTE | FOLL_FAST_ONLY))) + if (WARN_ON_ONCE(gup_flags & INTERNAL_GUP_FLAGS)) return false;
gup_flags |= to_set; diff --git a/mm/internal.h b/mm/internal.h index 30cf724ddbce3..50cf76d30a88f 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -964,6 +964,9 @@ enum { FOLL_UNLOCKABLE = 1 << 21, };
+#define INTERNAL_GUP_FLAGS (FOLL_TOUCH | FOLL_TRIED | FOLL_REMOTE | FOLL_PIN | \ + FOLL_FAST_ONLY | FOLL_UNLOCKABLE) + /* * Indicates for which pages that are write-protected in the page table, * whether GUP has to trigger unsharing via FAULT_FLAG_UNSHARE such that the