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charset="UTF-8" X-Rspam-User: X-Stat-Signature: aoog1sbtzrbw7g16bgsrjgb756wjad67 X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 4573A14000D X-HE-Tag: 1790617324-757126 X-HE-Meta: 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 nfxEq2QQ 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: When CONFIG_ARCH_HAS_VARIABLE_STACK_SIZE is enabled, the kernel stack may not be fully populated with the THREAD_SIZE virtual area. Teach task_stack_size() to return the size of the vm area and not a fixed size. This propagates to end_of_stack() which makes functions like stack_not_used() and set_task_stack_end_magic() to use the lowest valid stack address instead of THREAD_SIZE which would cause data aborts. Signed-off-by: Mostafa Saleh --- arch/Kconfig | 10 ++++++++++ include/linux/sched/task_stack.h | 5 +++++ 2 files changed, 15 insertions(+) diff --git a/arch/Kconfig b/arch/Kconfig index 45c657772362..d6fa2ccb0599 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -431,6 +431,16 @@ config HAVE_ASM_MODVERSIONS to support the module versioning for symbols exported from assembly code. +config ARCH_HAS_VARIABLE_STACK_SIZE + bool + depends on VMAP_STACK + depends on !STACK_GROWSUP + depends on THREAD_INFO_IN_TASK + help + An arch should select this if it supports dynamically configuring the + kernel stack size. + For example the kernel stack size can be from the command line. + config HAVE_REGS_AND_STACK_ACCESS_API bool help diff --git a/include/linux/sched/task_stack.h b/include/linux/sched/task_stack.h index 4a808f9c4631..07d73adaecd1 100644 --- a/include/linux/sched/task_stack.h +++ b/include/linux/sched/task_stack.h @@ -10,6 +10,7 @@ #include #include #include +#include #ifdef CONFIG_THREAD_INFO_IN_TASK @@ -96,6 +97,10 @@ static inline unsigned long *end_of_stack(const struct task_struct *p) */ static __always_inline unsigned long task_stack_size(const struct task_struct *task) { +#ifdef CONFIG_ARCH_HAS_VARIABLE_STACK_SIZE + if (task->stack_vm_area) + return task->stack_vm_area->nr_pages * PAGE_SIZE; +#endif return THREAD_SIZE; } -- 2.56.0.rc1.315.gc6ed9934b7-goog