summaryrefslogtreecommitdiff
path: root/arch/arm
diff options
context:
space:
mode:
authorArd Biesheuvel <ardb@kernel.org>2021-10-29 19:45:32 +0300
committerRussell King (Oracle) <rmk+kernel@armlinux.org.uk>2021-10-30 13:24:36 +0300
commitfa191b711c32ba107cf8d3474cd860407b7e997a (patch)
tree9c3e7f819f8f78e7acaf00cc34c77d147b754a76 /arch/arm
parent13a695aa50de151ff9aca868c3915687771c80a5 (diff)
downloadlinux-fa191b711c32ba107cf8d3474cd860407b7e997a.tar.xz
ARM: 9150/1: Fix PID_IN_CONTEXTIDR regression when THREAD_INFO_IN_TASK=y
The code that implements the rarely used PID_IN_CONTEXTIDR feature dereferences the 'task' field of struct thread_info directly, and this is no longer possible when THREAD_INFO_IN_TASK=y, as the 'task' field is omitted from the struct definition in that case. Instead, we should just cast the thread_info pointer to a task_struct pointer, given that the former is now the first member of the latter. So use a helper that abstracts this, and provide implementations for both cases. Reported by: Arnd Bergmann <arnd@arndb.de> Fixes: 18ed1c01a7dd ("ARM: smp: Enable THREAD_INFO_IN_TASK") Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm')
-rw-r--r--arch/arm/include/asm/thread_info.h11
-rw-r--r--arch/arm/mm/context.c2
2 files changed, 12 insertions, 1 deletions
diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index 787511396f3f..164e15f26485 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -79,9 +79,20 @@ struct thread_info {
#ifdef CONFIG_THREAD_INFO_IN_TASK
#define INIT_THREAD_INFO_TASK(tsk)
+
+static inline struct task_struct *thread_task(struct thread_info* ti)
+{
+ return (struct task_struct *)ti;
+}
+
#else
#define INIT_THREAD_INFO_TASK(tsk) .task = &(tsk),
+static inline struct task_struct *thread_task(struct thread_info* ti)
+{
+ return ti->task;
+}
+
/*
* how to get the thread information struct from C
*/
diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c
index b7525b433f3e..48091870db89 100644
--- a/arch/arm/mm/context.c
+++ b/arch/arm/mm/context.c
@@ -109,7 +109,7 @@ static int contextidr_notifier(struct notifier_block *unused, unsigned long cmd,
if (cmd != THREAD_NOTIFY_SWITCH)
return NOTIFY_DONE;
- pid = task_pid_nr(thread->task) << ASID_BITS;
+ pid = task_pid_nr(thread_task(thread)) << ASID_BITS;
asm volatile(
" mrc p15, 0, %0, c13, c0, 1\n"
" and %0, %0, %2\n"