| Message ID | 20200326194130.KQt2jbeWd%akpm@linux-foundation.org |
|---|---|
| State | New |
| Headers | show |
| Series | + mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2.patch added to -mm tree | expand |
--- a/mm/sparse.c~mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2 +++ a/mm/sparse.c @@ -781,7 +781,11 @@ static void section_deactivate(unsigned ms->usage = NULL; } memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr); - /* Mark the section invalid */ + /* + * Mark the section invalid so that valid_section() + * return false. This prevents code from dereferencing + * ms->usage array. + */ ms->section_mem_map &= ~SECTION_HAS_MEM_MAP; }
The patch titled Subject: mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2 has been added to the -mm tree. Its filename is mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: "Aneesh Kumar K.V" <aneesh.kumar@linux.ibm.com> Subject: mm-sparse-fix-kernel-crash-with-pfn_section_valid-check-v2 add comment Link: http://lkml.kernel.org/r/20200326133235.343616-1-aneesh.kumar@linux.ibm.com Fixes: d41e2f3bd546 ("mm/hotplug: fix hot remove failure in SPARSEMEM|!VMEMMAP case") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com> Reviewed-by: Baoquan He <bhe@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Dan Williams <dan.j.williams@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Wei Yang <richardw.yang@linux.intel.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Mike Rapoport <rppt@linux.ibm.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> --- mm/sparse.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)