From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 421DF30D41D; Wed, 29 Jul 2026 04:15:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785298518; cv=none; b=bdokIoZL3erPCMCFNY1RG9k/dq6qJVO9FpoT6cZf3w0ul9kEiHSdCbdjkYWsHTgDdlO+eyxFC5eEZ+7ufMkcacuvSm015bXddmb0ICmmZBKIpeQtVkkwllMEr6/qQaMPfMIznXjgMblK25Xp86DsDGyJRKyQ893rLvPxxLFNPLg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785298518; c=relaxed/simple; bh=cXaMpqb/PpsdDXrfKIaPIg2zZ+nYgWDoDeECDgx2BqQ=; h=Date:To:From:Subject:Message-Id; b=imtvUPgrB5t7Dt/KNkHmAZ0SgeCn0dYcfaC5v/bms74ymzpX2xWpnQdHatdepoqQwvyLciPkiphyYLeRLVPFlTWZXQSJWY3TkjPDEVb98K9lJJ/n2VTv78+xH063Dg96AdZHt2gVxpeL551JiELBn7F8HVZVnFfVIvkHXfuqZfo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=t+itcU+q; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="t+itcU+q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 154E21F000E9; Wed, 29 Jul 2026 04:15:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=korg; t=1785298514; bh=t6wxgisNNHAskks76xOX7Los/ry5afU4xQb+ksR9Cig=; h=Date:To:From:Subject; b=t+itcU+qnB5P+mdVX+wnftY1KK0ZV4YStkSVkPDfp7sRSB4kGVexB6hQURPutAZej Qw7qGZuiOZfPJ7PqpZy66L51eG45WCgca6Q0P051e9d1CSzh7mUf7IOXi0Dc57FKWm NQbxmnyeUFiyk56vUoGTQbQywEZqmnb6uUtddEaI= Date: Tue, 28 Jul 2026 21:15:13 -0700 To: mm-commits@vger.kernel.org,zenghui.yu@linux.dev,stable@vger.kernel.org,sj@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] samples-damon-wsse-stop-and-free-damon-ctx-when-damon_call-fails.patch removed from -mm tree Message-Id: <20260729041514.154E21F000E9@smtp.kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: samples/damon/wsse: stop and free damon ctx when damon_call() fails has been removed from the -mm tree. Its filename was samples-damon-wsse-stop-and-free-damon-ctx-when-damon_call-fails.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: SJ Park Subject: samples/damon/wsse: stop and free damon ctx when damon_call() fails Date: Sun, 28 Jun 2026 14:54:44 -0700 damon_sample_wsse_start() calls damon_call() right after damon_start() is succeeded. The kdamond that has started by the damon_start() could be terminated by itself before or in the middle of the damon_call() execution. There could be multiple reasons for such a stop including monitoring target process termination and kdamond_fn() internal memory allocation failures. In the case, damon_call() will fail and return an error without cleaning up the DAMON context object. The damon_sample_wsse_start() caller assumes it would clean up the object, though. When the user requests to start DAMON again, damon_sample_wsse_start() is called again, allocates a new DAMON context object and overwrites the pointer for the previous object. As a result, the previous context object is leaked. Safely stop the kdamond and deallocate the context object when the failure is returned. Note that the kdamond should be stopped first, because damon_call() failure means not complete termination of the kdamond but only the fact that the termination process has started. The user impact shouldn't be that significant because the race is not easy to happen, and only up to one DAMON context object can be leaked per race. The issue was discovered [1] by Sashiko. Link: https://lore.kernel.org/20260628215447.96166-6-sj@kernel.org Link: https://lore.kernel.org/20260610034828.4632-1-sj@kernel.org [1] Fixes: cc9c1b8c205b ("samples/damon/wsse: use damon_call() repeat mode instead of damon_callback") Signed-off-by: SJ Park Reviewed-by: Zenghui Yu Cc: # 6.17.x Signed-off-by: Andrew Morton --- samples/damon/wsse.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/samples/damon/wsse.c~samples-damon-wsse-stop-and-free-damon-ctx-when-damon_call-fails +++ a/samples/damon/wsse.c @@ -92,7 +92,12 @@ static int damon_sample_wsse_start(void) return err; } repeat_call_control.data = ctx; - return damon_call(ctx, &repeat_call_control); + err = damon_call(ctx, &repeat_call_control); + if (err) { + damon_stop(&ctx, 1); + damon_destroy_ctx(ctx); + } + return err; } static void damon_sample_wsse_stop(void) _ Patches currently in -mm which might be from sj@kernel.org are mm-damon-adjust-isolated-pages-stat-for-damos_migrate_hotcold.patch docs-mm-damon-design-update-for-damos_quota_node_eligible_mem_bp.patch docs-abi-damon-document-probe-files.patch mm-damon-tests-core-kunit-test-damon_rand.patch selftests-damon-sysfssh-test-multiple-probe-dirs-creation.patch selftests-damon-sysfssh-test-coreops_filters-directories.patch selftests-damon-sysfssh-test-dests-dir.patch selftests-damon-sysfssh-test-all-files-in-quota-goal-dir.patch mm-damon-core-reduce-range-setup-in-damon_commit_target_regions.patch mm-damon-sysfs-split-probe-setup-function-out.patch mm-damon-sysfs-split-out-filters-setup-function.patch mm-damon-sysfs-fix-typos-in-probe_addrm_dirs-s-attr-probe.patch mm-damon-core-introduce-damon_nr_accesses_mvsum.patch mm-damon-tests-core-kunit-test-damon_mvsum.patch mm-damon-core-always-update-last_nr_accesses-for-intervals-change.patch mm-damon-core-handle-unreset-nr_accesses-in-damon_nr_accesses_mvsum.patch mm-damon-core-use-damon_nr_accesses_mvsum-in-__damos_valid_target.patch mm-damon-core-use-damon_nr_accesses_mvsum-for-damos-region-tracing.patch mm-damon-sysfs-schemes-use-damon_nr_accesses_mvsum-for-damo-regions.patch mm-damon-core-remove-damon_warn_fix_nr_accesses_corruption.patch mm-damon-core-remove-damon_verify_reset_aggregated.patch mm-damon-core-remove-damon_verify_merge_regions_of.patch mm-damon-tests-core-kunit-remove-nr_accesses_bp-setup-and-tests.patch selftests-damon-drgn_dump_damon_status-do-not-dump-nr_accesses_bp.patch mm-damon-core-remove-nr_accesses_bp-setups-and-updates.patch mm-damon-core-remove-attrs-param-from-damon_update_region_access_rate.patch mm-damon-paddr-remove-attrs-param-from-__damon_pa_check_access.patch mm-damon-vaddr-remove-attrs-param-from-__damon_va_check_access.patch mm-damon-core-remove-damon_moving_sum-and-its-unit-test.patch mm-damon-core-remove-damon_region-nr_accesses_bp.patch mm-damon-add-damon_region-last_probe_hits.patch mm-damon-core-introduce-damon_probe_hits_mvsum.patch mm-damon-sysfs-schemes-set-probe-hits-as-pseudo-moving-sums.patch mm-damon-core-safely-validate-src-on-damon_commit_ctx.patch mm-damon-core-do-parameter-testing-commit-on-damon_start.patch mm-damon-sysfs-remove-duplicated-commit-input-validity-check.patch mm-damon-reclaim-remove-duplicated-min_region_sz-power-of-2-check.patch mm-damon-lru_sort-remove-duplicated-min_region_sz-power_of_2-check.patch mm-damon-document-region-size-validation-in-damon_set_regions.patch mm-damon-core-remove-start-end-check-in-damon_set_region_system_rams.patch mm-damon-sysfs-remove-region-size-validation.patch mm-damon-core-stop-ctxs-in-damon_start-before-returning-an-error.patch samples-damon-mtier-do-not-stop-first-context-for-damon_start-failure.patch mm-damon-core-make-damon_stop-never-fails.patch mm-damon-sysfs-ignore-damon_stop-return-value.patch mm-damon-reclaaim-ignore-damon_stop-return-value.patch mm-damon-lru_sort-ignore-damon_stop-return-value.patch mm-damon-core-change-damon_stop-return-type-to-void.patch samples-damon-mtier-stop-all-contexts-with-single-damon_stop-call.patch mm-damon-core-wait-ctx-stop-in-damon_call-before-reruning-an-error.patch samples-damon-wsse-do-not-stop-ctx-for-damon_call-failure.patch samples-damon-prcl-do-not-stop-damon-for-damon_call-failure.patch mm-damon-core-remove-comment-and-test-for-nr_to_bp-divide-by-zero.patch mm-damon-core-s-damon_max_nr_accesses-damon_nr_samples_per_aggr.patch mm-damon-core-s-accesses_bp_to_nr_accesses-sample_bp_to_count.patch mm-damon-core-s-nr_accesses_to_accesses_bp-sample_count_to_bp.patch mm-damon-core-s-nr_accesses_for_new_attrs-nr_samples_for_new_attrs.patch mm-damon-core-update-probe-hits-for-new-parameter-commit.patch mm-damon-core-handle-unreset-probe_hits-in-probe_hits_mvsum.patch mm-damon-core-introduce-damon_probe-weight.patch mm-damon-core-ask-apply_probes-ops-callback-to-set-sampling-address.patch mm-damon-paddr-set-samples-in-apply_probes-if-requested.patch mm-damon-core-ask-apply_probe-to-return-max-probe-hits-weighted-sum.patch mm-damon-core-implement-damon_probe_hits_wsum.patch mm-damon-paddr-respect-return_max_wsum.patch mm-damon-core-use-abs_diff-instead-of-abs.patch mm-damon-core-extend-merge-function-to-work-with-probe-hits.patch mm-damon-core-disallow-probe_hits-overflow-on-attrs-only-monitoring.patch mm-damon-core-validate-params-for-probe-hits-weighted-sum-overflow.patch mm-damon-core-disable-access-monitoring-when-probe-weights-are-set.patch mm-damon-core-set-samples-in-apply_probes-if-probe-weights-are-set.patch mm-damon-core-s-max_nr_accesses-max_merge_score-in-kdamond_fn.patch mm-damon-core-get-merge-threshold-from-probe-hits-when-weights-are-set.patch mm-damon-core-implement-damon_has_probe_weight.patch mm-damon-sysfs-implement-probe-weight-file.patch docs-mm-damon-design-document-attrs-only-monitoring.patch docs-admin-guide-mm-damon-usage-document-weight-sysfs-file.patch docs-abi-damon-document-probe-weight-file.patch mm-damon-core-skip-aging-from-repeated-aggressive-merging.patch mm-damon-core-hide-private-damon_region-fields.patch mm-damon-core-hide-private-damon_target-fields.patch mm-damon-core-hide-private-damos_quota_goal-fields.patch mm-damon-core-hide-private-damos_quota-fields.patch mm-damon-core-hide-private-damos_filter-fields.patch mm-damon-core-hide-private-damos-fields.patch mm-damon-core-hide-private-damon_filter-fields.patch mm-damon-core-hide-private-damon_probe-fields.patch mm-damon-sysfs-do-not-directly-access-damon_ctx-ops.patch mm-damon-core-hide-core-private-damon_ctx-fields.patch mm-damon-core-avoid-infinite-kdamond_merge_regions-internal-loop.patch mm-damon-tests-core-kunit-catch-test-failure-in-test_merge_regions_of.patch mm-damon-vaddr-drop-last-same-folio-access-check-optimization.patch mm-damon-paddr-drop-last-same-folio-access-check-reuse-optimization.patch mm-damon-sysfs-read-addr_unit-only-once-in-damon_sysfs_apply_inputs.patch mm-damon-sysfs-read-ops_id-only-once-in-damon_sysfs_apply_inputs.patch mm-damon-core-initialize-damos-last_applied.patch mm-damon-core-kunit-check-region-count-before-testing-in-split_at.patch mm-damon-vaddr-kunit-check-region-count-in-three_regions-test.patch mm-damon-core-kunit-handle-region-split-failure-in-filter_out.patch mm-damon-core-kunit-skip-wrong-dest-walk-in-commit_dests_for.patch mm-damon-core-kunit-skip-wrong-quota-goal-walk-in-commit_quota_goals.patch mm-damon-core-kunit-skip-wrong-region-walk-in-commit_target_regions.patch mm-damon-ops-common-use-nr_accesses-moving-sum-for-quota-score.patch mm-damon-core-handle-region-split-failure-in-apply_min_nr_regions.patch