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From:   "Paul E. McKenney" <paulmck@kernel.org>
To:     rcu@vger.kernel.org
Cc:     linux-kernel@vger.kernel.org, kernel-team@meta.com,
        rostedt@goodmis.org, "Paul E. McKenney" <paulmck@kernel.org>
Subject: [PATCH rcu 2/4] scftorture: Forgive memory-allocation failure if KASAN
Date:   Mon, 17 Jul 2023 11:18:18 -0700
Message-Id: <20230717181820.1098541-2-paulmck@kernel.org>
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References: <38be0135-a7a4-4c16-b2c6-1b3817c3067f@paulmck-laptop>
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Kernels built with CONFIG_KASAN=y quarantine newly freed memory in order
to better detect use-after-free errors.  However, this can exhaust memory
more quickly in allocator-heavy tests, which can result in spurious
scftorture failure.  This commit therefore forgives memory-allocation
failure in kernels built with CONFIG_KASAN=y, but continues counting
the errors for use in detailed test-result analyses.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
 kernel/scftorture.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/kernel/scftorture.c b/kernel/scftorture.c
index 5d113aa59e77..83c33ba0ca7e 100644
--- a/kernel/scftorture.c
+++ b/kernel/scftorture.c
@@ -171,7 +171,8 @@ static void scf_torture_stats_print(void)
 		scfs.n_all_wait += scf_stats_p[i].n_all_wait;
 	}
 	if (atomic_read(&n_errs) || atomic_read(&n_mb_in_errs) ||
-	    atomic_read(&n_mb_out_errs) || atomic_read(&n_alloc_errs))
+	    atomic_read(&n_mb_out_errs) ||
+	    (!IS_ENABLED(CONFIG_KASAN) && atomic_read(&n_alloc_errs)))
 		bangstr = "!!! ";
 	pr_alert("%s %sscf_invoked_count %s: %lld resched: %lld single: %lld/%lld single_ofl: %lld/%lld single_rpc: %lld single_rpc_ofl: %lld many: %lld/%lld all: %lld/%lld ",
 		 SCFTORT_FLAG, bangstr, isdone ? "VER" : "ver", invoked_count, scfs.n_resched,
@@ -323,7 +324,8 @@ static void scftorture_invoke_one(struct scf_statistics *scfp, struct torture_ra
 		preempt_disable();
 	if (scfsp->scfs_prim == SCF_PRIM_SINGLE || scfsp->scfs_wait) {
 		scfcp = kmalloc(sizeof(*scfcp), GFP_ATOMIC);
-		if (WARN_ON_ONCE(!scfcp)) {
+		if (!scfcp) {
+			WARN_ON_ONCE(!IS_ENABLED(CONFIG_KASAN));
 			atomic_inc(&n_alloc_errs);
 		} else {
 			scfcp->scfc_cpu = -1;
-- 
2.40.1