From fa191b711c32ba107cf8d3474cd860407b7e997a Mon Sep 17 00:00:00 2001 From: Ard Biesheuvel Date: Fri, 29 Oct 2021 17:45:32 +0100 Subject: 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 Fixes: 18ed1c01a7dd ("ARM: smp: Enable THREAD_INFO_IN_TASK") Signed-off-by: Ard Biesheuvel Signed-off-by: Russell King (Oracle) --- arch/arm/include/asm/thread_info.h | 11 +++++++++++ arch/arm/mm/context.c | 2 +- 2 files changed, 12 insertions(+), 1 deletion(-) 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" -- cgit v1.2.3