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Accessing > mapping->flags in this state leads directly to a NULL pointer > dereference. > > This commit fixes the issue by moving the check for mapping != NULL > before any attempt to access mapping->flags. > > Fixes: c010d47f107f ("mm: thp: split huge page to any lower order pages") > Signed-off-by: Wei Yang > Cc: Zi Yan > Cc: "David Hildenbrand (Red Hat)" > Cc: > > --- > This patch is based on current mm-new, latest commit: > > febb34c02328 dt-bindings: riscv: Add Svrsw60t59b extension description > > v2: > * just move folio->mapping ahead > --- > mm/huge_memory.c | 22 ++++++++++------------ > 1 file changed, 10 insertions(+), 12 deletions(-) > Thanks. Reviewed-by: Zi Yan Best Regards, Yan, Zi