On 2/13/25 19:17, Lorenzo Stoakes wrote: > Extend the guard region self tests to explicitly assert that guard regions > work correctly for functionality specific to file-backed and shmem > mappings. > > In addition to testing all of the existing guard region functionality that > is currently tested against anonymous mappings against file-backed and > shmem mappings (except those which are exclusive to anonymous mapping), we > now also: > > * Test that MADV_SEQUENTIAL does not cause unexpected readahead behaviour. > * Test that MAP_PRIVATE behaves as expected with guard regions installed in > both a shared and private mapping of an fd. > * Test that a read-only file can correctly establish guard regions. > * Test a probable fault-around case does not interfere with guard regions > (or vice-versa). > * Test that truncation does not eliminate guard regions. > * Test that hole punching functions as expected in the presence of guard > regions. > * Test that a read-only mapping of a memfd write sealed mapping can have > guard regions established within it and function correctly without > violation of the seal. > * Test that guard regions installed into a mapping of the anonymous zero > page function correctly. Impressive. > Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx>
