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Baoquan He
ede27b7ee2
Patch series "mm/gup: Minor fix, cleanup and improvements", v4. These were made from code inspection in mm/gup.c. This patch (of 3): In __get_user_pages(), it will traverse page table and take a reference to the page the given user address corresponds to if GUP_GET or GUP_PIN is set. However, it's not supported both GUP_GET and GUP_PIN are set. Even though this check need be done, it should be done earlier, but not doing it till entering into follow_page_pte() and failed. Furthermore, this checking has been done in is_valid_gup_args() and all external users of __get_user_pages() will call is_valid_gup_args() to catch the illegal setting. We don't need to worry about internal users of __get_user_pages() because the gup_flags are set by MM code correctly. Here remove the checking in follow_page_pte(), and add VM_WARN_ON_ONCE() to catch the possible exceptional setting just in case. And also change the VM_BUG_ON to VM_WARN_ON_ONCE() for checking (!!pages != !!(gup_flags & (FOLL_GET | FOLL_PIN))) because the checking has been done in is_valid_gup_args() for external users of __get_user_pages(). Link: https://lkml.kernel.org/r/20250410035717.473207-1-bhe@redhat.com Link: https://lkml.kernel.org/r/20250410035717.473207-3-bhe@redhat.com Signed-off-by: Baoquan He <bhe@redhat.com> Reviewed-by: Oscar Salvador <osalvador@suse.de> Acked-by: David Hildenbrand <david@redhat.com> Cc: Yanjun.Zhu <yanjun.zhu@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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