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Date: Mon, 15 Sep 2025 20:33:03 +0530 Message-ID: X-Mailer: git-send-email 2.51.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=OMsn3TaB c=1 sm=1 tr=0 ts=68c82ab5 cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=yJojWOMRYYMA:10 a=VwQbUJbxAAAA:8 a=VnNF1IyMAAAA:8 a=8dabxjvEmk4eI1i_HKQA:9 X-Proofpoint-ORIG-GUID: O6Pn4dbXVKFzHep12KWTtyqNC5MstEit X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwOTEzMDAwMSBTYWx0ZWRfX6FjBQv4Cc3yL yXvdYlJcNW8w/DURJa/TjchGcLgafZnS657WUjiiBosfIWYiEH37DyZLczSImTdSlvBC5Gw/zzF TY9a9hGCFEen6mJsdk93t1jghZtfxjRAmfn9yJ1tFj8vH6EtNu+LAbo3rQZlfhdSwWSV0lGB2qc nFlqntk/ChiBLdGKPcwO1t/tNNFr5vdyvHpzcOs6sCQ8+E6GBdlKObdqPPBPqX331HBV65gKSFy 6JXZEevzEu2o/8q1rfHFAc0NI4BAKdZENeWE1gAtQFsM1R1vZuTxzcIaSDWYPspozqp5zoH6wN/ AD0CPvSKoyUsR4NnPCJEvXbizIUDg6eCUfmKIkQw89ZuMXdZTjd9nIIcb+Rpay78nSsB/KB31cF UAP/QrWV X-Proofpoint-GUID: 9AwENwd4pSzlgdVpYoJ6_4Q0WypDhWZf X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-09-15_05,2025-09-12_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 suspectscore=0 spamscore=0 priorityscore=1501 adultscore=0 impostorscore=0 clxscore=1015 malwarescore=0 bulkscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2509130001 The first patch in this series fixes the incorrect accounting of KSM counters such as ksm_merging_pages, ksm_rmap_items, and the global ksm_zero_pages during fork. The following two patches add selftests to verify that the ksm_merging_pages counter and the global ksm_zero_pages counter are updated correctly during fork. Test Results ============ Without the first patch ----------------------- # [RUN] test_fork_ksm_merging_page_count not ok 10 ksm_merging_page in child: 32 # [RUN] test_fork_global_ksm_zero_pages_count not ok 11 Incorrect global ksm zero page counter after fork With the first patch -------------------- # [RUN] test_fork_ksm_merging_page_count ok 10 ksm_merging_pages is not inherited after fork # [RUN] test_fork_global_ksm_zero_pages_count ok 11 Global ksm zero page count is correct after fork Changes: v1 -> v2 : - Rebased to mm-new branch - Fixed incorrect global ksm_zero_pages counter issue during fork and added a selftest to verify it. v1: https://lore.kernel.org/all/2e662107e01417bf9af23bc7f52863cd538419be.1756211338.git.donettom@linux.ibm.com/ Donet Tom (3): mm/ksm: Fix incorrect KSM counter handling in mm_struct during fork selftests/mm: Added fork inheritance test for ksm_merging_pages counter selftests/mm: Added fork test to verify global ksm_zero_pages counter behavior include/linux/ksm.h | 8 +- .../selftests/mm/ksm_functional_tests.c | 114 +++++++++++++++++- 2 files changed, 120 insertions(+), 2 deletions(-) -- 2.51.0