[prev in list] [next in list] [prev in thread] [next in thread] 

List:       linux-mips
Subject:    [PATCH v2 06/13] MIPS: fix MSA context for tasks which don't use FP first
From:       Paul Burton <paul.burton () imgtec ! com>
Date:       2014-07-31 13:53:16
Message-ID: 1406814796-8109-1-git-send-email-paul.burton () imgtec ! com
[Download RAW message or body]

If a task does not execute scalar FP instructions prior to using MSA
then the flags indicating that the task has live MSA context were not
being set. The upper 64b of each vector register would then be lost
upon the tasks first context switch after using MSA.

Signed-off-by: Paul Burton <paul.burton@imgtec.com>
---
Changes in v2:
  - Rebase atop v2 of patch 5 as requested by Ralf.
---
 arch/mips/kernel/traps.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
index 4aca484..00f3143 100644
--- a/arch/mips/kernel/traps.c
+++ b/arch/mips/kernel/traps.c
@@ -1096,6 +1096,8 @@ static int enable_restore_fp_context(int msa)
 		if (msa && !err) {
 			enable_msa();
 			_init_msa_upper();
+			set_thread_flag(TIF_USEDMSA);
+			set_thread_flag(TIF_MSA_CTX_LIVE);
 		}
 		if (!err)
 			set_used_math();
-- 
2.0.2


[prev in list] [next in list] [prev in thread] [next in thread]