2009-06-09 14:06:25

by Chuck Ebbert

Subject: [patch] x86: clear TS in irq_ts_save() when in an atomic section

x86: clear TS in irq_ts_save() when in an atomic section

The dynamic FPU context allocation changes caused the padlock driver
to generate the below warning. Fix it by masking TS when doing padlock
encryption operations in an atomic section.

BUG: sleeping function called from invalid context at mm/slub.c:1602
in_atomic(): 1, irqs_disabled(): 0, pid: 82, name: cryptomgr_test
Pid: 82, comm: cryptomgr_test Not tainted 2.6.29.4-168.test7.fc11.x86_64 #1
Call Trace:
[<ffffffff8103ff16>] __might_sleep+0x10b/0x110
[<ffffffff810cd3b2>] kmem_cache_alloc+0x37/0xf1
[<ffffffff81018505>] init_fpu+0x49/0x8a
[<ffffffff81012a83>] math_state_restore+0x3e/0xbc
[<ffffffff813ac6d0>] do_device_not_available+0x9/0xb
[<ffffffff810123ab>] device_not_available+0x1b/0x20
[<ffffffffa001c066>] ? aes_crypt+0x66/0x74 [padlock_aes]
[<ffffffff8119a51a>] ? blkcipher_walk_next+0x257/0x2e0
[<ffffffff8119a731>] ? blkcipher_walk_first+0x18e/0x19d
[<ffffffffa001c1fe>] aes_encrypt+0x9d/0xe5 [padlock_aes]
[<ffffffffa0027253>] crypt+0x6b/0x114 [xts]
[<ffffffffa001c161>] ? aes_encrypt+0x0/0xe5 [padlock_aes]
[<ffffffffa001c161>] ? aes_encrypt+0x0/0xe5 [padlock_aes]
[<ffffffffa0027390>] encrypt+0x49/0x4b [xts]
[<ffffffff81199acc>] async_encrypt+0x3c/0x3e
[<ffffffff8119dafc>] test_skcipher+0x1da/0x658
[<ffffffff811979c3>] ? crypto_spawn_tfm+0x8e/0xb1
[<ffffffff8119672d>] ? __crypto_alloc_tfm+0x11b/0x15f
[<ffffffff811979c3>] ? crypto_spawn_tfm+0x8e/0xb1
[<ffffffff81199dbe>] ? skcipher_geniv_init+0x2b/0x47
[<ffffffff8119a905>] ? async_chainiv_init+0x5c/0x61
[<ffffffff8119dfdd>] alg_test_skcipher+0x63/0x9b
[<ffffffff8119e1bc>] alg_test+0x12d/0x175
[<ffffffff8119c488>] cryptomgr_test+0x38/0x54
[<ffffffff8119c450>] ? cryptomgr_test+0x0/0x54
[<ffffffff8105c6c9>] kthread+0x4d/0x78
[<ffffffff8101264a>] child_rip+0xa/0x20
[<ffffffff81011f67>] ? restore_args+0x0/0x30
[<ffffffff8105c67c>] ? kthread+0x0/0x78
[<ffffffff81012640>] ? child_rip+0x0/0x20

Signed-off-by: Chuck Ebbert <[email protected]>

--- work-2.6.29.4.orig/arch/x86/include/asm/i387.h
+++ work-2.6.29.4/arch/x86/include/asm/i387.h
@@ -305,18 +305,18 @@ static inline void kernel_fpu_end(void)
/*
* Some instructions like VIA's padlock instructions generate a spurious
* DNA fault but don't modify SSE registers. And these instructions
- * get used from interrupt context aswell. To prevent these kernel instructions
- * in interrupt context interact wrongly with other user/kernel fpu usage, we
+ * get used from interrupt context as well. To prevent these kernel instructions
+ * in interrupt context interacting wrongly with other user/kernel fpu usage, we
* should use them only in the context of irq_ts_save/restore()
*/
static inline int irq_ts_save(void)
{
/*
- * If we are in process context, we are ok to take a spurious DNA fault.
- * Otherwise, doing clts() in process context require pre-emption to
- * be disabled or some heavy lifting like kernel_fpu_begin()
+ * If in process context and not atomic, we can handle a spurious DNA fault.
+ * Otherwise, doing clts() in process context requires disabling preemption
+ * or some heavy lifting like kernel_fpu_begin()
*/
- if (!in_interrupt())
+ if (!in_atomic() && !in_interrupt())
return 0;

if (read_cr0() & X86_CR0_TS) {

2009-06-09 14:23:16

by Ingo Molnar

Subject: Re: [patch] x86: clear TS in irq_ts_save() when in an atomic section

* Chuck Ebbert <[email protected]> wrote:

> - if (!in_interrupt())
> + if (!in_atomic() && !in_interrupt())
> return 0;

since in_interrupt() implies in_atomic() (upstream), why not just
do:

if (!in_atomic())
return 0;

?

Ingo

2009-06-09 14:42:04

by Chuck Ebbert

Subject: [patch v2] x86: clear TS in irq_ts_save() when in an atomic section

x86: clear TS in irq_ts_save() when in atomic

The dynamic FPU context allocation changes caused the padlock driver
to generate the below warning. Fix it by masking TS when doing padlock
encryption operations in an atomic section.

BUG: sleeping function called from invalid context at mm/slub.c:1602
in_atomic(): 1, irqs_disabled(): 0, pid: 82, name: cryptomgr_test
Pid: 82, comm: cryptomgr_test Not tainted 2.6.29.4-168.test7.fc11.x86_64 #1
Call Trace:
[<ffffffff8103ff16>] __might_sleep+0x10b/0x110
[<ffffffff810cd3b2>] kmem_cache_alloc+0x37/0xf1
[<ffffffff81018505>] init_fpu+0x49/0x8a
[<ffffffff81012a83>] math_state_restore+0x3e/0xbc
[<ffffffff813ac6d0>] do_device_not_available+0x9/0xb
[<ffffffff810123ab>] device_not_available+0x1b/0x20
[<ffffffffa001c066>] ? aes_crypt+0x66/0x74 [padlock_aes]
[<ffffffff8119a51a>] ? blkcipher_walk_next+0x257/0x2e0
[<ffffffff8119a731>] ? blkcipher_walk_first+0x18e/0x19d
[<ffffffffa001c1fe>] aes_encrypt+0x9d/0xe5 [padlock_aes]
[<ffffffffa0027253>] crypt+0x6b/0x114 [xts]
[<ffffffffa001c161>] ? aes_encrypt+0x0/0xe5 [padlock_aes]
[<ffffffffa001c161>] ? aes_encrypt+0x0/0xe5 [padlock_aes]
[<ffffffffa0027390>] encrypt+0x49/0x4b [xts]
[<ffffffff81199acc>] async_encrypt+0x3c/0x3e
[<ffffffff8119dafc>] test_skcipher+0x1da/0x658
[<ffffffff811979c3>] ? crypto_spawn_tfm+0x8e/0xb1
[<ffffffff8119672d>] ? __crypto_alloc_tfm+0x11b/0x15f
[<ffffffff811979c3>] ? crypto_spawn_tfm+0x8e/0xb1
[<ffffffff81199dbe>] ? skcipher_geniv_init+0x2b/0x47
[<ffffffff8119a905>] ? async_chainiv_init+0x5c/0x61
[<ffffffff8119dfdd>] alg_test_skcipher+0x63/0x9b
[<ffffffff8119e1bc>] alg_test+0x12d/0x175
[<ffffffff8119c488>] cryptomgr_test+0x38/0x54
[<ffffffff8119c450>] ? cryptomgr_test+0x0/0x54
[<ffffffff8105c6c9>] kthread+0x4d/0x78
[<ffffffff8101264a>] child_rip+0xa/0x20
[<ffffffff81011f67>] ? restore_args+0x0/0x30
[<ffffffff8105c67c>] ? kthread+0x0/0x78
[<ffffffff81012640>] ? child_rip+0x0/0x20

Signed-off-by: Chuck Ebbert <[email protected]>

--- work-2.6.29.4.orig/arch/x86/include/asm/i387.h
+++ work-2.6.29.4/arch/x86/include/asm/i387.h
@@ -305,18 +305,18 @@ static inline void kernel_fpu_end(void)
/*
* Some instructions like VIA's padlock instructions generate a spurious
* DNA fault but don't modify SSE registers. And these instructions
- * get used from interrupt context aswell. To prevent these kernel instructions
- * in interrupt context interact wrongly with other user/kernel fpu usage, we
+ * get used from interrupt context as well. To prevent these kernel instructions
+ * in interrupt context interacting wrongly with other user/kernel fpu usage, we
* should use them only in the context of irq_ts_save/restore()
*/
static inline int irq_ts_save(void)
{
/*
- * If we are in process context, we are ok to take a spurious DNA fault.
- * Otherwise, doing clts() in process context require pre-emption to
- * be disabled or some heavy lifting like kernel_fpu_begin()
+ * If in process context and not atomic, we can take a spurious DNA fault.
+ * Otherwise, doing clts() in process context requires disabling preemption
+ * or some heavy lifting like kernel_fpu_begin()
*/
- if (!in_interrupt())
+ if (!in_atomic())
return 0;

if (read_cr0() & X86_CR0_TS) {

2009-06-09 14:54:00

by Chuck Ebbert

Subject: [tip:x86/urgent] x86: Clear TS in irq_ts_save() when in an atomic section

Commit-ID: 0b8c3d5ab000c22889af7f9409799a6cdc31a2b2
Gitweb: http://git.kernel.org/tip/0b8c3d5ab000c22889af7f9409799a6cdc31a2b2
Author: Chuck Ebbert <[email protected]>
AuthorDate: Tue, 9 Jun 2009 10:40:50 -0400
Committer: Ingo Molnar <[email protected]>
CommitDate: Tue, 9 Jun 2009 16:50:43 +0200

x86: Clear TS in irq_ts_save() when in an atomic section

The dynamic FPU context allocation changes caused the padlock driver
to generate the below warning. Fix it by masking TS when doing padlock
encryption operations in an atomic section.

This solves:

BUG: sleeping function called from invalid context at mm/slub.c:1602
in_atomic(): 1, irqs_disabled(): 0, pid: 82, name: cryptomgr_test
Pid: 82, comm: cryptomgr_test Not tainted 2.6.29.4-168.test7.fc11.x86_64 #1
Call Trace:
[<ffffffff8103ff16>] __might_sleep+0x10b/0x110
[<ffffffff810cd3b2>] kmem_cache_alloc+0x37/0xf1
[<ffffffff81018505>] init_fpu+0x49/0x8a
[<ffffffff81012a83>] math_state_restore+0x3e/0xbc
[<ffffffff813ac6d0>] do_device_not_available+0x9/0xb
[<ffffffff810123ab>] device_not_available+0x1b/0x20
[<ffffffffa001c066>] ? aes_crypt+0x66/0x74 [padlock_aes]
[<ffffffff8119a51a>] ? blkcipher_walk_next+0x257/0x2e0
[<ffffffff8119a731>] ? blkcipher_walk_first+0x18e/0x19d
[<ffffffffa001c1fe>] aes_encrypt+0x9d/0xe5 [padlock_aes]
[<ffffffffa0027253>] crypt+0x6b/0x114 [xts]
[<ffffffffa001c161>] ? aes_encrypt+0x0/0xe5 [padlock_aes]
[<ffffffffa001c161>] ? aes_encrypt+0x0/0xe5 [padlock_aes]
[<ffffffffa0027390>] encrypt+0x49/0x4b [xts]
[<ffffffff81199acc>] async_encrypt+0x3c/0x3e
[<ffffffff8119dafc>] test_skcipher+0x1da/0x658
[<ffffffff811979c3>] ? crypto_spawn_tfm+0x8e/0xb1
[<ffffffff8119672d>] ? __crypto_alloc_tfm+0x11b/0x15f
[<ffffffff811979c3>] ? crypto_spawn_tfm+0x8e/0xb1
[<ffffffff81199dbe>] ? skcipher_geniv_init+0x2b/0x47
[<ffffffff8119a905>] ? async_chainiv_init+0x5c/0x61
[<ffffffff8119dfdd>] alg_test_skcipher+0x63/0x9b
[<ffffffff8119e1bc>] alg_test+0x12d/0x175
[<ffffffff8119c488>] cryptomgr_test+0x38/0x54
[<ffffffff8119c450>] ? cryptomgr_test+0x0/0x54
[<ffffffff8105c6c9>] kthread+0x4d/0x78
[<ffffffff8101264a>] child_rip+0xa/0x20
[<ffffffff81011f67>] ? restore_args+0x0/0x30
[<ffffffff8105c67c>] ? kthread+0x0/0x78
[<ffffffff81012640>] ? child_rip+0x0/0x20

Signed-off-by: Chuck Ebbert <[email protected]>
Cc: Suresh Siddha <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>


---
arch/x86/include/asm/i387.h | 12 ++++++------
1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h
index 71c9e51..4aab52f 100644
--- a/arch/x86/include/asm/i387.h
+++ b/arch/x86/include/asm/i387.h
@@ -305,18 +305,18 @@ static inline void kernel_fpu_end(void)
/*
* Some instructions like VIA's padlock instructions generate a spurious
* DNA fault but don't modify SSE registers. And these instructions
- * get used from interrupt context aswell. To prevent these kernel instructions
- * in interrupt context interact wrongly with other user/kernel fpu usage, we
+ * get used from interrupt context as well. To prevent these kernel instructions
+ * in interrupt context interacting wrongly with other user/kernel fpu usage, we
* should use them only in the context of irq_ts_save/restore()
*/
static inline int irq_ts_save(void)
{
/*
- * If we are in process context, we are ok to take a spurious DNA fault.
- * Otherwise, doing clts() in process context require pre-emption to
- * be disabled or some heavy lifting like kernel_fpu_begin()
+ * If in process context and not atomic, we can take a spurious DNA fault.
+ * Otherwise, doing clts() in process context requires disabling preemption
+ * or some heavy lifting like kernel_fpu_begin()
*/
- if (!in_interrupt())
+ if (!in_atomic())
return 0;

if (read_cr0() & X86_CR0_TS) {