Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751635AbbEGAZQ (ORCPT ); Wed, 6 May 2015 20:25:16 -0400 Received: from gate.crashing.org ([63.228.1.57]:53898 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751158AbbEGAZL (ORCPT ); Wed, 6 May 2015 20:25:11 -0400 Message-ID: <1430958109.3453.23.camel@kernel.crashing.org> Subject: Re: [PATCH RFC 13/15] powerpc: enable_kernel_altivec() requires disabled preemption From: Benjamin Herrenschmidt To: David Hildenbrand Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, peterz@infradead.org, yang.shi@windriver.com, bigeasy@linutronix.de, paulus@samba.org, akpm@linux-foundation.org, heiko.carstens@de.ibm.com, schwidefsky@de.ibm.com, borntraeger@de.ibm.com, mst@redhat.com, tglx@linutronix.de, David.Laight@ACULAB.COM, hughd@google.com, hocko@suse.cz, ralf@linux-mips.org, herbert@gondor.apana.org.au, linux@arm.linux.org.uk, airlied@linux.ie, daniel.vetter@intel.com, linux-mm@kvack.org, linux-arch@vger.kernel.org Date: Thu, 07 May 2015 10:21:49 +1000 In-Reply-To: <1430934639-2131-14-git-send-email-dahi@linux.vnet.ibm.com> References: <1430934639-2131-1-git-send-email-dahi@linux.vnet.ibm.com> <1430934639-2131-14-git-send-email-dahi@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11-0ubuntu3 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7389 Lines: 209 On Wed, 2015-05-06 at 19:50 +0200, David Hildenbrand wrote: > enable_kernel_altivec() has to be called with disabled preemption. > Let's make this explicit, to prepare for pagefault_disable() not > touching preemption anymore. > > Signed-off-by: David Hildenbrand Acked-by: Benjamin Herrenschmidt > --- > arch/powerpc/lib/vmx-helper.c | 11 ++++++----- > drivers/crypto/vmx/aes.c | 8 +++++++- > drivers/crypto/vmx/aes_cbc.c | 6 ++++++ > drivers/crypto/vmx/ghash.c | 8 ++++++++ > 4 files changed, 27 insertions(+), 6 deletions(-) > > diff --git a/arch/powerpc/lib/vmx-helper.c b/arch/powerpc/lib/vmx-helper.c > index 3cf529c..ac93a3b 100644 > --- a/arch/powerpc/lib/vmx-helper.c > +++ b/arch/powerpc/lib/vmx-helper.c > @@ -27,11 +27,11 @@ int enter_vmx_usercopy(void) > if (in_interrupt()) > return 0; > > - /* This acts as preempt_disable() as well and will make > - * enable_kernel_altivec(). We need to disable page faults > - * as they can call schedule and thus make us lose the VMX > - * context. So on page faults, we just fail which will cause > - * a fallback to the normal non-vmx copy. > + preempt_disable(); > + /* > + * We need to disable page faults as they can call schedule and > + * thus make us lose the VMX context. So on page faults, we just > + * fail which will cause a fallback to the normal non-vmx copy. > */ > pagefault_disable(); > > @@ -47,6 +47,7 @@ int enter_vmx_usercopy(void) > int exit_vmx_usercopy(void) > { > pagefault_enable(); > + preempt_enable(); > return 0; > } > > diff --git a/drivers/crypto/vmx/aes.c b/drivers/crypto/vmx/aes.c > index ab300ea..a9064e3 100644 > --- a/drivers/crypto/vmx/aes.c > +++ b/drivers/crypto/vmx/aes.c > @@ -78,12 +78,14 @@ static int p8_aes_setkey(struct crypto_tfm *tfm, const u8 *key, > int ret; > struct p8_aes_ctx *ctx = crypto_tfm_ctx(tfm); > > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); > ret += aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key); > pagefault_enable(); > - > + preempt_enable(); > + > ret += crypto_cipher_setkey(ctx->fallback, key, keylen); > return ret; > } > @@ -95,10 +97,12 @@ static void p8_aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) > if (in_interrupt()) { > crypto_cipher_encrypt_one(ctx->fallback, dst, src); > } else { > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > aes_p8_encrypt(src, dst, &ctx->enc_key); > pagefault_enable(); > + preempt_enable(); > } > } > > @@ -109,10 +113,12 @@ static void p8_aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src) > if (in_interrupt()) { > crypto_cipher_decrypt_one(ctx->fallback, dst, src); > } else { > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > aes_p8_decrypt(src, dst, &ctx->dec_key); > pagefault_enable(); > + preempt_enable(); > } > } > > diff --git a/drivers/crypto/vmx/aes_cbc.c b/drivers/crypto/vmx/aes_cbc.c > index 1a559b7..477284a 100644 > --- a/drivers/crypto/vmx/aes_cbc.c > +++ b/drivers/crypto/vmx/aes_cbc.c > @@ -79,11 +79,13 @@ static int p8_aes_cbc_setkey(struct crypto_tfm *tfm, const u8 *key, > int ret; > struct p8_aes_cbc_ctx *ctx = crypto_tfm_ctx(tfm); > > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > ret = aes_p8_set_encrypt_key(key, keylen * 8, &ctx->enc_key); > ret += aes_p8_set_decrypt_key(key, keylen * 8, &ctx->dec_key); > pagefault_enable(); > + preempt_enable(); > > ret += crypto_blkcipher_setkey(ctx->fallback, key, keylen); > return ret; > @@ -106,6 +108,7 @@ static int p8_aes_cbc_encrypt(struct blkcipher_desc *desc, > if (in_interrupt()) { > ret = crypto_blkcipher_encrypt(&fallback_desc, dst, src, nbytes); > } else { > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > > @@ -119,6 +122,7 @@ static int p8_aes_cbc_encrypt(struct blkcipher_desc *desc, > } > > pagefault_enable(); > + preempt_enable(); > } > > return ret; > @@ -141,6 +145,7 @@ static int p8_aes_cbc_decrypt(struct blkcipher_desc *desc, > if (in_interrupt()) { > ret = crypto_blkcipher_decrypt(&fallback_desc, dst, src, nbytes); > } else { > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > > @@ -154,6 +159,7 @@ static int p8_aes_cbc_decrypt(struct blkcipher_desc *desc, > } > > pagefault_enable(); > + preempt_enable(); > } > > return ret; > diff --git a/drivers/crypto/vmx/ghash.c b/drivers/crypto/vmx/ghash.c > index d0ffe27..f255ec4 100644 > --- a/drivers/crypto/vmx/ghash.c > +++ b/drivers/crypto/vmx/ghash.c > @@ -114,11 +114,13 @@ static int p8_ghash_setkey(struct crypto_shash *tfm, const u8 *key, > if (keylen != GHASH_KEY_LEN) > return -EINVAL; > > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > enable_kernel_fp(); > gcm_init_p8(ctx->htable, (const u64 *) key); > pagefault_enable(); > + preempt_enable(); > return crypto_shash_setkey(ctx->fallback, key, keylen); > } > > @@ -140,23 +142,27 @@ static int p8_ghash_update(struct shash_desc *desc, > } > memcpy(dctx->buffer + dctx->bytes, src, > GHASH_DIGEST_SIZE - dctx->bytes); > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > enable_kernel_fp(); > gcm_ghash_p8(dctx->shash, ctx->htable, dctx->buffer, > GHASH_DIGEST_SIZE); > pagefault_enable(); > + preempt_enable(); > src += GHASH_DIGEST_SIZE - dctx->bytes; > srclen -= GHASH_DIGEST_SIZE - dctx->bytes; > dctx->bytes = 0; > } > len = srclen & ~(GHASH_DIGEST_SIZE - 1); > if (len) { > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > enable_kernel_fp(); > gcm_ghash_p8(dctx->shash, ctx->htable, src, len); > pagefault_enable(); > + preempt_enable(); > src += len; > srclen -= len; > } > @@ -180,12 +186,14 @@ static int p8_ghash_final(struct shash_desc *desc, u8 *out) > if (dctx->bytes) { > for (i = dctx->bytes; i < GHASH_DIGEST_SIZE; i++) > dctx->buffer[i] = 0; > + preempt_disable(); > pagefault_disable(); > enable_kernel_altivec(); > enable_kernel_fp(); > gcm_ghash_p8(dctx->shash, ctx->htable, dctx->buffer, > GHASH_DIGEST_SIZE); > pagefault_enable(); > + preempt_enable(); > dctx->bytes = 0; > } > memcpy(out, dctx->shash, GHASH_DIGEST_SIZE); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/