Re: [PATCH v2 2/2] powerpc: Do not assign thread.tidr if already assigned
From: Andrew Donnellan <hidden>
Date: 2017-11-27 01:06:19
On 24/11/17 19:33, Vaibhav Jain wrote:
If set_thread_tidr() is called twice for same task_struct then it will
allocate a new tidr value to it leaving the previous value still
dangling in the vas_thread_ida table.
To fix this the patch changes set_thread_tidr() to check if a tidr
value is already assigned to the task_struct and if yes then returns
the existing value from function instead of allocating a new one.
Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR")
Signed-off-by: Vaibhav Jain <redacted>Reviewed-by: Andrew Donnellan <redacted>
quoted hunk ↗ jump to hunk
--- v2 -> Fix minor spell errors in patch description --- arch/powerpc/kernel/process.c | 3 +++ 1 file changed, 3 insertions(+)diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 5d8176c7c2d8..9a72282b022d 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c@@ -1577,6 +1577,9 @@ int set_thread_tidr(struct task_struct *t) if (t != current) return -EINVAL; + if (t->thread.tidr) + return t->thread.tidr; + rc = assign_thread_tidr(); if (rc > 0) { t->thread.tidr = rc;
-- Andrew Donnellan OzLabs, ADL Canberra andrew.donnellan@au1.ibm.com IBM Australia Limited