Revert "powerpc: Do not call ppc_md.panic in fadump panic notifier"

This reverts commit a3b2cb30f252b21a6f962e0dd107c8b897ca65e4.

That commit tried to fix problems with panic on powerpc in certain
circumstances, where some output from the generic panic code was being
dropped.

Unfortunately, it breaks things worse in other circumstances. In
particular when running a PAPR guest, it will now attempt to reboot
instead of informing the hypervisor (KVM or PowerVM) that the guest
has crashed. The crash notification is important to some
virtualization management layers.

Revert it for now until we can come up with a better solution.

Fixes: a3b2cb30f252 ("powerpc: Do not call ppc_md.panic in fadump panic notifier")
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
[mpe: Tweak change log a bit]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index 73b92017b6d7b5231cd8c9d46b7986bb9131f12c..cd2fc1cc1cc7c056255b6f49effefb1e6d0cc1e6 100644 (file)
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -76,6 +76,7 @@ struct machdep_calls {
 
        void __noreturn (*restart)(char *cmd);
        void __noreturn (*halt)(void);
+       void            (*panic)(char *str);
        void            (*cpu_die)(void);
 
        long            (*time_init)(void); /* Optional, may be NULL */

diff --git a/arch/powerpc/include/asm/setup.h b/arch/powerpc/include/asm/setup.h
index 257d23dbf55dce902644334280e9d72b3ff91ba8..cf00ec26303aef1415c7d5fcd7425f2149ac0295 100644 (file)
--- a/arch/powerpc/include/asm/setup.h
+++ b/arch/powerpc/include/asm/setup.h
@@ -24,6 +24,7 @@ extern void reloc_got2(unsigned long);
 
 void check_for_initrd(void);
 void initmem_init(void);
+void setup_panic(void);
 #define ARCH_PANIC_TIMEOUT 180
 
 #ifdef CONFIG_PPC_PSERIES

diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 04ea5c04fd24825a6c6affc4d7d6956b30321b84..3c2c2688918fffdcfbdbb64e2ec2f1b0dfe1ccf9 100644 (file)
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -1462,25 +1462,6 @@ static void fadump_init_files(void)
        return;
 }
 
-static int fadump_panic_event(struct notifier_block *this,
-                             unsigned long event, void *ptr)
-{
-       /*
-        * If firmware-assisted dump has been registered then trigger
-        * firmware-assisted dump and let firmware handle everything
-        * else. If this returns, then fadump was not registered, so
-        * go through the rest of the panic path.
-        */
-       crash_fadump(NULL, ptr);
-
-       return NOTIFY_DONE;
-}
-
-static struct notifier_block fadump_panic_block = {
-       .notifier_call = fadump_panic_event,
-       .priority = INT_MIN /* may not return; must be done last */
-};
-
 /*
  * Prepare for firmware-assisted dump.
  */
@@ -1513,9 +1494,6 @@ int __init setup_fadump(void)
                init_fadump_mem_struct(&fdm, fw_dump.reserve_dump_area_start);
        fadump_init_files();
 
-       atomic_notifier_chain_register(&panic_notifier_list,
-                                       &fadump_panic_block);
-
        return 1;
 }
 subsys_initcall(setup_fadump);

diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c
index 2075322cd22522edf7de78e32ef2679fae8e9913..9d213542a48bb91360b7b540ef429473494ebe98 100644 (file)
--- a/arch/powerpc/kernel/setup-common.c
+++ b/arch/powerpc/kernel/setup-common.c
@@ -704,6 +704,30 @@ int check_legacy_ioport(unsigned long base_port)
 }
 EXPORT_SYMBOL(check_legacy_ioport);
 
+static int ppc_panic_event(struct notifier_block *this,
+                             unsigned long event, void *ptr)
+{
+       /*
+        * If firmware-assisted dump has been registered then trigger
+        * firmware-assisted dump and let firmware handle everything else.
+        */
+       crash_fadump(NULL, ptr);
+       ppc_md.panic(ptr);  /* May not return */
+       return NOTIFY_DONE;
+}
+
+static struct notifier_block ppc_panic_block = {
+       .notifier_call = ppc_panic_event,
+       .priority = INT_MIN /* may not return; must be done last */
+};
+
+void __init setup_panic(void)
+{
+       if (!ppc_md.panic)
+               return;
+       atomic_notifier_chain_register(&panic_notifier_list, &ppc_panic_block);
+}
+
 #ifdef CONFIG_CHECK_CACHE_COHERENCY
 /*
  * For platforms that have configurable cache-coherency.  This function
@@ -848,6 +872,9 @@ void __init setup_arch(char **cmdline_p)
        /* Probe the machine type, establish ppc_md. */
        probe_machine();
 
+       /* Setup panic notifier if requested by the platform. */
+       setup_panic();
+
        /*
         * Configure ppc_md.power_save (ppc32 only, 64-bit machines do
         * it from their respective probe() function.

diff --git a/arch/powerpc/platforms/ps3/setup.c b/arch/powerpc/platforms/ps3/setup.c
index 9dabea6e14439647b726d007a63de63a853ac3d0..6244bc849469e33af7dcc5a4ac2b21dd970ac1c6 100644 (file)
--- a/arch/powerpc/platforms/ps3/setup.c
+++ b/arch/powerpc/platforms/ps3/setup.c
@@ -104,6 +104,20 @@ static void __noreturn ps3_halt(void)
        ps3_sys_manager_halt(); /* never returns */
 }
 
+static void ps3_panic(char *str)
+{
+       DBG("%s:%d %s\n", __func__, __LINE__, str);
+
+       smp_send_stop();
+       printk("\n");
+       printk("   System does not reboot automatically.\n");
+       printk("   Please press POWER button.\n");
+       printk("\n");
+
+       while(1)
+               lv1_pause(1);
+}
+
 #if defined(CONFIG_FB_PS3) || defined(CONFIG_FB_PS3_MODULE) || \
     defined(CONFIG_PS3_FLASH) || defined(CONFIG_PS3_FLASH_MODULE)
 static void __init prealloc(struct ps3_prealloc *p)
@@ -255,6 +269,7 @@ define_machine(ps3) {
        .probe                          = ps3_probe,
        .setup_arch                     = ps3_setup_arch,
        .init_IRQ                       = ps3_init_IRQ,
+       .panic                          = ps3_panic,
        .get_boot_time                  = ps3_get_boot_time,
        .set_dabr                       = ps3_set_dabr,
        .calibrate_decr                 = ps3_calibrate_decr,

diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 5f1beb8367acaa4562dbc647ad06a1f4c12a8f72..a8531e01265842f39e759bc59aa67f3afd461486 100644 (file)
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -726,6 +726,7 @@ define_machine(pseries) {
        .pcibios_fixup          = pSeries_final_fixup,
        .restart                = rtas_restart,
        .halt                   = rtas_halt,
+       .panic                  = rtas_os_term,
        .get_boot_time          = rtas_get_boot_time,
        .get_rtc_time           = rtas_get_rtc_time,
        .set_rtc_time           = rtas_set_rtc_time,