From mboxrd@z Thu Jan 1 00:00:00 1970 From: srivatsa.bhat@linux.vnet.ibm.com (Srivatsa S. Bhat) Date: Tue, 22 Jan 2013 13:08:52 +0530 Subject: [PATCH v5 21/45] crypto: pcrypt - Protect access to cpu_online_mask with get/put_online_cpus() In-Reply-To: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> References: <20130122073210.13822.50434.stgit@srivatsabhat.in.ibm.com> Message-ID: <20130122073848.13822.35451.stgit@srivatsabhat.in.ibm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org The pcrypt_aead_init_tfm() function access the cpu_online_mask without disabling CPU hotplug. And it looks like it can afford to sleep, so use the get/put_online_cpus() APIs to protect against CPU hotplug. Cc: Steffen Klassert Cc: Herbert Xu Cc: "David S. Miller" Cc: linux-crypto at vger.kernel.org Signed-off-by: Srivatsa S. Bhat --- crypto/pcrypt.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/crypto/pcrypt.c b/crypto/pcrypt.c index b2c99dc..10f64e2 100644 --- a/crypto/pcrypt.c +++ b/crypto/pcrypt.c @@ -280,12 +280,16 @@ static int pcrypt_aead_init_tfm(struct crypto_tfm *tfm) ictx->tfm_count++; + get_online_cpus(); + cpu_index = ictx->tfm_count % cpumask_weight(cpu_online_mask); ctx->cb_cpu = cpumask_first(cpu_online_mask); for (cpu = 0; cpu < cpu_index; cpu++) ctx->cb_cpu = cpumask_next(ctx->cb_cpu, cpu_online_mask); + put_online_cpus(); + cipher = crypto_spawn_aead(crypto_instance_ctx(inst)); if (IS_ERR(cipher))