diff options
| author | Ard Biesheuvel <ardb@kernel.org> | 2021-10-29 17:45:32 +0100 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2021-10-30 11:24:36 +0100 |
| commit | fa191b711c32ba107cf8d3474cd860407b7e997a (patch) | |
| tree | 9c3e7f819f8f78e7acaf00cc34c77d147b754a76 | |
| parent | 13a695aa50de151ff9aca868c3915687771c80a5 (diff) | |
| download | lwn-fa191b711c32ba107cf8d3474cd860407b7e997a.tar.gz lwn-fa191b711c32ba107cf8d3474cd860407b7e997a.zip | |
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>
| -rw-r--r-- | arch/arm/include/asm/thread_info.h | 11 | ||||
| -rw-r--r-- | arch/arm/mm/context.c | 2 |
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" |