Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:

 - Fix for transparent huge page change_protection() logic which was
   inadvertently changing a huge pmd page into a pmd table entry.

 - Function graph tracer panic fix caused by the return_to_handler code
   corrupting the multi-regs function return value (composite types).

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: ftrace: fix function_graph tracer panic
  arm64: Fix THP protection change logic

2 files changed, 22 insertions, 4 deletions

diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index b0329be95cb1..26b066690593 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -79,7 +79,7 @@ extern void __pgd_error(const char *file, int line, unsigned long val);
 #define PAGE_S2                 __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_NORMAL) | PTE_S2_RDONLY)
 #define PAGE_S2_DEVICE          __pgprot(PROT_DEFAULT | PTE_S2_MEMATTR(MT_S2_DEVICE_nGnRE) | PTE_S2_RDONLY | PTE_UXN)
 
-#define PAGE_NONE               __pgprot(((_PAGE_DEFAULT) & ~PTE_TYPE_MASK) | PTE_PROT_NONE | PTE_PXN | PTE_UXN)
+#define PAGE_NONE               __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_PXN | PTE_UXN)
 #define PAGE_SHARED             __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE)
 #define PAGE_SHARED_EXEC        __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_WRITE)
 #define PAGE_COPY               __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_NG | PTE_PXN | PTE_UXN)
@@ -496,7 +496,7 @@ static inline pud_t *pud_offset(pgd_t *pgd, unsigned long addr)
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
         const pteval_t mask = PTE_USER | PTE_PXN | PTE_UXN | PTE_RDONLY |
-                              PTE_PROT_NONE | PTE_WRITE | PTE_TYPE_MASK;
+                              PTE_PROT_NONE | PTE_VALID | PTE_WRITE;
         /* preserve the hardware dirty information */
         if (pte_hw_dirty(pte))
                 pte = pte_mkdirty(pte);
diff --git a/arch/arm64/kernel/entry-ftrace.S b/arch/arm64/kernel/entry-ftrace.S
index 08cafc518b9a..0f03a8fe2314 100644
--- a/arch/arm64/kernel/entry-ftrace.S
+++ b/arch/arm64/kernel/entry-ftrace.S
@@ -178,6 +178,24 @@ ENTRY(ftrace_stub)
 ENDPROC(ftrace_stub)
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
+        /* save return value regs*/
+        .macro save_return_regs
+        sub sp, sp, #64
+        stp x0, x1, [sp]
+        stp x2, x3, [sp, #16]
+        stp x4, x5, [sp, #32]
+        stp x6, x7, [sp, #48]
+        .endm
+
+        /* restore return value regs*/
+        .macro restore_return_regs
+        ldp x0, x1, [sp]
+        ldp x2, x3, [sp, #16]
+        ldp x4, x5, [sp, #32]
+        ldp x6, x7, [sp, #48]
+        add sp, sp, #64
+        .endm
+
 /*
  * void ftrace_graph_caller(void)
  *
@@ -204,11 +222,11 @@ ENDPROC(ftrace_graph_caller)
  * only when CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST is enabled.
  */
 ENTRY(return_to_handler)
-        str     x0, [sp, #-16]!
+        save_return_regs
         mov     x0, x29                 //     parent's fp
         bl      ftrace_return_to_handler// addr = ftrace_return_to_hander(fp);
         mov     x30, x0                 // restore the original return address
-        ldr     x0, [sp], #16
+        restore_return_regs
         ret
 END(return_to_handler)
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */