Ran into this while looking at some new crypto code using FPU
hitting a WARN_ON_ONCE(!irq_fpu_usable()) in the kernel_fpu_begin()
on a x86 kernel that uses the new eagerfpu model. In short, current eagerfpu
changes return 0 for interrupted_kernel_fpu_idle() and the in_interrupt()
thinks it is in the interrupt context because of the local_bh_disable().
Thus resulting in the WARN_ON().
Remove the local_bh_disable/enable() calls around the existing
local_irq_disable/enable() calls. local_irq_disable/enable() already
disables the BH.
[ If there are any other legitimate users calling kernel_fpu_begin() from
the process context but with BH disabled, then we can look into fixing the
irq_fpu_usable() in future. ]
Signed-off-by: Suresh Siddha <suresh.b.sid...@intel.com>
Cc: Tim Chen <tim.c.c...@linux.intel.com>
---
crypto/tcrypt.c | 6 ------
1 files changed, 0 insertions(+), 6 deletions(-)
diff --git a/crypto/tcrypt.c b/crypto/tcrypt.c
index 5cf2ccb..de8c5d3 100644
--- a/crypto/tcrypt.c
+++ b/crypto/tcrypt.c
@@ -97,7 +97,6 @@ static int test_cipher_cycles(struct blkcipher_desc *desc,
int enc,
int ret = 0;
int i;
- local_bh_disable();
local_irq_disable();
/* Warm-up run. */
@@ -130,7 +129,6 @@ static int test_cipher_cycles(struct blkcipher_desc *desc,
int enc,
out:
local_irq_enable();
- local_bh_enable();
if (ret == 0)
printk("1 operation in %lu cycles (%d bytes)\n",
@@ -300,7 +298,6 @@ static int test_hash_cycles_digest(struct hash_desc *desc,
int i;
int ret;
- local_bh_disable();
local_irq_disable();
/* Warm-up run. */
@@ -327,7 +324,6 @@ static int test_hash_cycles_digest(struct hash_desc *desc,
out:
local_irq_enable();
- local_bh_enable();
if (ret)
return ret;
@@ -348,7 +344,6 @@ static int test_hash_cycles(struct hash_desc *desc, struct
scatterlist *sg,
if (plen == blen)
return test_hash_cycles_digest(desc, sg, blen, out);
- local_bh_disable();
local_irq_disable();
/* Warm-up run. */
@@ -391,7 +386,6 @@ static int test_hash_cycles(struct hash_desc *desc, struct
scatterlist *sg,
out:
local_irq_enable();
- local_bh_enable();
if (ret)
return ret;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
