xtensa: fix access to THREAD_RA/THREAD_SP/THREAD_DS

With SMP and a lot of debug options enabled task_struct::thread gets out
of reach of s32i/l32i instructions with base pointing at task_struct,
breaking build with the following messages:

  arch/xtensa/kernel/entry.S: Assembler messages:
  arch/xtensa/kernel/entry.S:1002: Error: operand 3 of 'l32i.n' has invalid value '1048'
  arch/xtensa/kernel/entry.S:1831: Error: operand 3 of 's32i.n' has invalid value '1040'
  arch/xtensa/kernel/entry.S:1832: Error: operand 3 of 's32i.n' has invalid value '1044'

Change base to point to task_struct::thread in such cases.
Don't use a10 in _switch_to to save/restore prev pointer as a2 is not
clobbered.

Cc: stable@vger.kernel.org
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
This commit is contained in:
Max Filippov
2014-07-27 07:23:41 +04:00
parent 89f77c6f5b
commit 5224712374
2 changed files with 13 additions and 4 deletions

View File

@@ -52,7 +52,12 @@
*/
.macro get_fs ad, sp
GET_CURRENT(\ad,\sp)
#if THREAD_CURRENT_DS > 1020
addi \ad, \ad, TASK_THREAD
l32i \ad, \ad, THREAD_CURRENT_DS - TASK_THREAD
#else
l32i \ad, \ad, THREAD_CURRENT_DS
#endif
.endm
/*