From a5a05b91c7f36c180c32e27fa41890957c31bad1 Mon Sep 17 00:00:00 2001
From: Hari Bathini <hbathini@linux.vnet.ibm.com>
Date: Thu, 1 Jun 2017 22:52:10 +0530
Subject: [PATCH] powerpc/fadump: provide a helpful error message
References: bsc#1037669
Patch-mainline: v4.13-rc1
Git-commit: a5a05b91c7f36c180c32e27fa41890957c31bad1
fadump fails to register when there are holes in boot memory area.
Provide a helpful error message to the user in such case.
Signed-off-by: Hari Bathini <hbathini@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/kernel/fadump.c | 36 ++++++++++++++++++++++++++++++++++++
1 file changed, 36 insertions(+)
diff --git a/arch/powerpc/kernel/fadump.c b/arch/powerpc/kernel/fadump.c
index 750bff3b4af3..a3568136ab28 100644
--- a/arch/powerpc/kernel/fadump.c
+++ b/arch/powerpc/kernel/fadump.c
@@ -130,6 +130,38 @@ int is_fadump_active(void)
return fw_dump.dump_active;
}
+/*
+ * Returns 1, if there are no holes in boot memory area,
+ * 0 otherwise.
+ */
+static int is_boot_memory_area_contiguous(void)
+{
+ struct memblock_region *reg;
+ unsigned long tstart, tend;
+ unsigned long start_pfn = PHYS_PFN(RMA_START);
+ unsigned long end_pfn = PHYS_PFN(RMA_START + fw_dump.boot_memory_size);
+ unsigned int ret = 0;
+
+ for_each_memblock(memory, reg) {
+ tstart = max(start_pfn, memblock_region_memory_base_pfn(reg));
+ tend = min(end_pfn, memblock_region_memory_end_pfn(reg));
+ if (tstart < tend) {
+ /* Memory hole from start_pfn to tstart */
+ if (tstart > start_pfn)
+ break;
+
+ if (tend == end_pfn) {
+ ret = 1;
+ break;
+ }
+
+ start_pfn = tend + 1;
+ }
+ }
+
+ return ret;
+}
+
/* Print firmware assisted dump configurations for debugging purpose. */
static void fadump_show_config(void)
{
@@ -457,6 +489,10 @@ static int register_fw_dump(struct fadump_mem_struct *fdm)
" dump. Hardware Error(%d).\n", rc);
break;
case -3:
+ if (!is_boot_memory_area_contiguous())
+ pr_err("Can't have holes in boot memory area while "
+ "registering fadump\n");
+
printk(KERN_ERR "Failed to register firmware-assisted kernel"
" dump. Parameter Error(%d).\n", rc);
err = -EINVAL;
--
2.10.2