From: Vaibhav Jain Date: Fri, 24 Nov 2017 08:33:38 +0000 (+0530) Subject: powerpc: Do not assign thread.tidr if already assigned X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=7e4d4233260be0611c7fbdb2730c12731c4b8dc0;p=openwrt%2Fstaging%2Fblogic.git powerpc: Do not assign thread.tidr if already assigned 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 zero. Fixes: ec233ede4c86("powerpc: Add support for setting SPRN_TIDR") Signed-off-by: Vaibhav Jain Reviewed-by: Andrew Donnellan [mpe: Modify to return 0 in the success case, not the TID value] Signed-off-by: Michael Ellerman --- diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index d205b52e3850..5acb5a176dbe 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 0; + rc = assign_thread_tidr(); if (rc < 0) return rc;