sh: Fix argument page dcache flushing regression.

In the do_execve() path, argument page handling used to explicitly call flush_dcache_page() for each page, this has since been reworked and uses flush_kernel_dcache_page() instead, which is presently a nop. Doing a simple modprobe/rmmod in a loop under busybox consistently manages to crash without providing a sane flush_kernel_dcache_page() implementation, so, plug in a simple implementation. Signed-off-by: Carmelo Amoroso <carmelo73@gmail.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>

sh: Fix argument page dcache flushing regression.
In the do_execve() path, argument page handling used to explicitly call flush_dcache_page() for each page, this has since been reworked and uses flush_kernel_dcache_page() instead, which is presently a nop. Doing a simple modprobe/rmmod in a loop under busybox consistently manages to crash without providing a sane flush_kernel_dcache_page() implementation, so, plug in a simple implementation. Signed-off-by: Carmelo Amoroso <carmelo73@gmail.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Carmelo Amoroso · Paul Mundt
1 parent 3ce5445046
Showing 1 changed file with 6 additions and 0 deletions Side-by-side Diff
include/asm-sh/cacheflush.h
@@ -43,6 +43,12 @@
 extern void __flush_invalidate_region(void *start, int size);
 #endif
  
+#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
+static inline void flush_kernel_dcache_page(struct page *page)
+{
+	flush_dcache_page(page);
+}
+
 #if defined(CONFIG_CPU_SH4) && !defined(CONFIG_CACHE_OFF)
 extern void copy_to_user_page(struct vm_area_struct *vma,
 	struct page *page, unsigned long vaddr, void *dst, const void *src,
...	...	@@ -43,6 +43,12 @@
43	43	extern void __flush_invalidate_region(void *start, int size);
44	44	#endif
45	45
	46	+#define ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
	47	+static inline void flush_kernel_dcache_page(struct page *page)
	48	+{
	49	+ flush_dcache_page(page);
	50	+}
	51	+
46	52	#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_CACHE_OFF)
47	53	extern void copy_to_user_page(struct vm_area_struct *vma,
48	54	struct page page, unsigned long vaddr, void dst, const void *src,