powerpc/ps3: Fix kexec shutdown hang

The ps3_mm_region_destroy() and ps3_mm_vas_destroy() routines
are called very late in the shutdown via kexec's mmu_cleanup_all
routine.  By the time mmu_cleanup_all runs it is too late to use
udbg_printf, and calling it will cause PS3 systems to hang.

Remove all debugging statements from ps3_mm_region_destroy() and
ps3_mm_vas_destroy() and replace any error reporting with calls
to lv1_panic.

With this change builds with 'DEBUG' defined will not cause kexec
reboots to hang, and builds with 'DEBUG' defined or not will end
in lv1_panic if an error is encountered.

Signed-off-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7325c4af2b4c989c19d6a26b90b1fec9c0615ddf.1589049250.git.geoff@infradead.org

diff --git a/arch/powerpc/platforms/ps3/mm.c b/arch/powerpc/platforms/ps3/mm.c
index b83f2c8..d094321 100644 (file)
--- a/arch/powerpc/platforms/ps3/mm.c
+++ b/arch/powerpc/platforms/ps3/mm.c
@@ -200,13 +200,14 @@ void ps3_mm_vas_destroy(void)
 {
        int result;
 
-       DBG("%s:%d: map.vas_id    = %llu\n", __func__, __LINE__, map.vas_id);
-
        if (map.vas_id) {
                result = lv1_select_virtual_address_space(0);
-               BUG_ON(result);
-               result = lv1_destruct_virtual_address_space(map.vas_id);
-               BUG_ON(result);
+               result += lv1_destruct_virtual_address_space(map.vas_id);
+
+               if (result) {
+                       lv1_panic(0);
+               }
+
                map.vas_id = 0;
        }
 }
@@ -304,19 +305,20 @@ static void ps3_mm_region_destroy(struct mem_region *r)
        int result;
 
        if (!r->destroy) {
-               pr_info("%s:%d: Not destroying high region: %llxh %llxh\n",
-                       __func__, __LINE__, r->base, r->size);
                return;
        }
 
-       DBG("%s:%d: r->base = %llxh\n", __func__, __LINE__, r->base);
-
        if (r->base) {
                result = lv1_release_memory(r->base);
-               BUG_ON(result);
+
+               if (result) {
+                       lv1_panic(0);
+               }
+
                r->size = r->base = r->offset = 0;
                map.total = map.rm.size;
        }
+
        ps3_mm_set_repository_highmem(NULL);
 }