From 2ee9e0150ed5068610d747d116fd9d0db9bd8118 Mon Sep 17 00:00:00 2001
Message-Id: <2ee9e0150ed5068610d747d116fd9d0db9bd8118.1594742966.git.zanussi@kernel.org>
In-Reply-To: <832f7d97d6b989a5b4860dd2dbec58ad6ad5ab81.1594742966.git.zanussi@kernel.org>
References: <832f7d97d6b989a5b4860dd2dbec58ad6ad5ab81.1594742966.git.zanussi@kernel.org>
From: Peter Zijlstra <peterz@infradead.org>
Date: Mon, 14 Nov 2011 18:19:27 +0100
Subject: [PATCH 220/329] x86: crypto: Reduce preempt disabled regions
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/4.19/older/patches-4.19.132-rt59.tar.xz

Restrict the preempt disabled regions to the actual floating point
operations and enable preemption for the administrative actions.

This is necessary on RT to avoid that kfree and other operations are
called with preemption disabled.

Reported-and-tested-by: Carsten Emde <cbe@osadl.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/crypto/aesni-intel_glue.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 917f25e4d0a8..58d8c03fc32d 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -434,14 +434,14 @@ static int ecb_encrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@@ -456,14 +456,14 @@ static int ecb_decrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@@ -478,14 +478,14 @@ static int cbc_encrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK, walk.iv);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@@ -500,14 +500,14 @@ static int cbc_decrypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes)) {
+		kernel_fpu_begin();
 		aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			      nbytes & AES_BLOCK_MASK, walk.iv);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
@@ -557,18 +557,20 @@ static int ctr_crypt(struct skcipher_request *req)
 
 	err = skcipher_walk_virt(&walk, req, true);
 
-	kernel_fpu_begin();
 	while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) {
+		kernel_fpu_begin();
 		aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr,
 			              nbytes & AES_BLOCK_MASK, walk.iv);
+		kernel_fpu_end();
 		nbytes &= AES_BLOCK_SIZE - 1;
 		err = skcipher_walk_done(&walk, nbytes);
 	}
 	if (walk.nbytes) {
+		kernel_fpu_begin();
 		ctr_crypt_final(ctx, &walk);
+		kernel_fpu_end();
 		err = skcipher_walk_done(&walk, 0);
 	}
-	kernel_fpu_end();
 
 	return err;
 }
-- 
2.17.1

