>> The recent commit adding VM_SHADOW_STACK for arm64 GCS did not update >> the /proc/[pid]/smaps display logic to show the "ss" flag for GCS pages. >> This patch adds the necessary condition to display "ss" flag. >> >> ... >> >> --- a/fs/proc/task_mmu.c >> +++ b/fs/proc/task_mmu.c >> @@ -994,6 +994,9 @@ static void show_smap_vma_flags(struct seq_file *m, struct vm_area_struct *vma) >> #ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK >> [ilog2(VM_SHADOW_STACK)] = "ss", >> #endif >> +#if defined(CONFIG_ARM64_GCS) >> + [ilog2(VM_SHADOW_STACK)] = "ss", >> +#endif >> #if defined(CONFIG_64BIT) || defined(CONFIG_PPC32) >> [ilog2(VM_DROPPABLE)] = "dp", >> #endif > > It is possible to have CONFIG_ARM64_GCS=y when > CONFIG_ARCH_HAS_USER_SHADOW_STACK=n? If so, is this a correct > combination? Hi, Morton After revisiting the code logic, I realized that if CONFIG_ARM64_GCS is enabled, CONFIG_ARCH_HAS_USER_SHADOW_STACK will always be enabled as well. Therefore, it seems unnecessary to add separate VM_SHADOW_STACK support specifically for CONFIG_ARM64_GCS at this stage. I will make sure to review future patches more carefully to avoid such oversights. Regards, Wang > > > Also, wouldn't it be nicer to code this as > > --- a/fs/proc/task_mmu.c~a > +++ a/fs/proc/task_mmu.c > @@ -991,7 +991,7 @@ static void show_smap_vma_flags(struct s > #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_MINOR > [ilog2(VM_UFFD_MINOR)] = "ui", > #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_MINOR */ > -#ifdef CONFIG_ARCH_HAS_USER_SHADOW_STACK > +#if defined(CONFIG_ARCH_HAS_USER_SHADOW_STACK) || defined(CONFIG_ARM64_GCS) > [ilog2(VM_SHADOW_STACK)] = "ss", > #endif > #if defined(CONFIG_64BIT) || defined(CONFIG_PPC32) > _ > --
