Merge tag 'powerpc-4.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...

[cascardo/linux.git] / arch / powerpc / kernel / machine_kexec_64.c

diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c
index 4c780a3..a205fa3 100644 (file)
--- a/arch/powerpc/kernel/machine_kexec_64.c
+++ b/arch/powerpc/kernel/machine_kexec_64.c
@@ -23,6 +23,7 @@
 #include <asm/current.h>
 #include <asm/machdep.h>
 #include <asm/cacheflush.h>
+#include <asm/firmware.h>
 #include <asm/paca.h>
 #include <asm/mmu.h>
 #include <asm/sections.h>      /* _end */
@@ -31,21 +32,6 @@
 #include <asm/hw_breakpoint.h>
 #include <asm/asm-prototypes.h>
 
-#ifdef CONFIG_PPC_BOOK3E
-int default_machine_kexec_prepare(struct kimage *image)
-{
-       int i;
-       /*
-        * Since we use the kernel fault handlers and paging code to
-        * handle the virtual mode, we must make sure no destination
-        * overlaps kernel static data or bss.
-        */
-       for (i = 0; i < image->nr_segments; i++)
-               if (image->segment[i].mem < __pa(_end))
-                       return -ETXTBSY;
-       return 0;
-}
-#else
 int default_machine_kexec_prepare(struct kimage *image)
 {
        int i;
@@ -55,9 +41,6 @@ int default_machine_kexec_prepare(struct kimage *image)
        const unsigned long *basep;
        const unsigned int *sizep;
 
-       if (!mmu_hash_ops.hpte_clear_all)
-               return -ENOENT;
-
        /*
         * Since we use the kernel fault handlers and paging code to
         * handle the virtual mode, we must make sure no destination
@@ -67,31 +50,6 @@ int default_machine_kexec_prepare(struct kimage *image)
                if (image->segment[i].mem < __pa(_end))
                        return -ETXTBSY;
 
-       /*
-        * For non-LPAR, we absolutely can not overwrite the mmu hash
-        * table, since we are still using the bolted entries in it to
-        * do the copy.  Check that here.
-        *
-        * It is safe if the end is below the start of the blocked
-        * region (end <= low), or if the beginning is after the
-        * end of the blocked region (begin >= high).  Use the
-        * boolean identity !(a || b)  === (!a && !b).
-        */
-#ifdef CONFIG_PPC_STD_MMU_64
-       if (htab_address) {
-               low = __pa(htab_address);
-               high = low + htab_size_bytes;
-
-               for (i = 0; i < image->nr_segments; i++) {
-                       begin = image->segment[i].mem;
-                       end = begin + image->segment[i].memsz;
-
-                       if ((begin < high) && (end > low))
-                               return -ETXTBSY;
-               }
-       }
-#endif /* CONFIG_PPC_STD_MMU_64 */
-
        /* We also should not overwrite the tce tables */
        for_each_node_by_type(node, "pci") {
                basep = of_get_property(node, "linux,tce-base", NULL);
@@ -113,7 +71,6 @@ int default_machine_kexec_prepare(struct kimage *image)
 
        return 0;
 }
-#endif /* !CONFIG_PPC_BOOK3E */
 
 static void copy_segments(unsigned long ind)
 {
@@ -332,11 +289,14 @@ struct paca_struct kexec_paca;
 /* Our assembly helper, in misc_64.S */
 extern void kexec_sequence(void *newstack, unsigned long start,
                           void *image, void *control,
-                          void (*clear_all)(void)) __noreturn;
+                          void (*clear_all)(void),
+                          bool copy_with_mmu_off) __noreturn;
 
 /* too late to fail here */
 void default_machine_kexec(struct kimage *image)
 {
+       bool copy_with_mmu_off;
+
        /* prepare control code if any */
 
        /*
@@ -374,18 +334,29 @@ void default_machine_kexec(struct kimage *image)
        /* XXX: If anyone does 'dynamic lppacas' this will also need to be
         * switched to a static version!
         */
+       /*
+        * On Book3S, the copy must happen with the MMU off if we are either
+        * using Radix page tables or we are not in an LPAR since we can
+        * overwrite the page tables while copying.
+        *
+        * In an LPAR, we keep the MMU on otherwise we can't access beyond
+        * the RMA. On BookE there is no real MMU off mode, so we have to
+        * keep it enabled as well (but then we have bolted TLB entries).
+        */
+#ifdef CONFIG_PPC_BOOK3E
+       copy_with_mmu_off = false;
+#else
+       copy_with_mmu_off = radix_enabled() ||
+               !(firmware_has_feature(FW_FEATURE_LPAR) ||
+                 firmware_has_feature(FW_FEATURE_PS3_LV1));
+#endif
 
        /* Some things are best done in assembly.  Finding globals with
         * a toc is easier in C, so pass in what we can.
         */
        kexec_sequence(&kexec_stack, image->start, image,
-                       page_address(image->control_code_page),
-#ifdef CONFIG_PPC_STD_MMU
-                       mmu_hash_ops.hpte_clear_all
-#else
-                       NULL
-#endif
-       );
+                      page_address(image->control_code_page),
+                      mmu_cleanup_all, copy_with_mmu_off);
        /* NOTREACHED */
 }