From f0e3acbcd3ba16d06d4f3e51b90655c69004768c Mon Sep 17 00:00:00 2001
Message-Id: <f0e3acbcd3ba16d06d4f3e51b90655c69004768c.1582043081.git.msuchanek@suse.de>
From: Hari Bathini <hbathini@linux.ibm.com>
Date: Fri, 28 Jun 2019 00:51:09 +0530
Subject: [PATCH rebased 1/2] powerpc: reserve memory for capture kernel after
hugepages init
Patch-mainline: submitted https://patchwork.ozlabs.org/patch/1240173/
References: bsc#1140025 ltc#176086
Sometimes, memory reservation for KDump/FADump can overlap with memory
marked for hugepages. This overlap leads to error, hang in KDump case
and copy error reported by f/w in case of FADump, while trying to
capture dump. Report error while setting up memory for the capture
kernel instead of running into issues while capturing dump, by moving
KDump/FADump reservation below MMU early init and failing gracefully
when hugepages memory overlaps with capture kernel memory.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/kernel/prom.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c
index 7159e79..454e19cf 100644
--- a/arch/powerpc/kernel/prom.c
+++ b/arch/powerpc/kernel/prom.c
@@ -731,14 +731,6 @@ void __init early_init_devtree(void *params)
if (PHYSICAL_START > MEMORY_START)
memblock_reserve(MEMORY_START, 0x8000);
reserve_kdump_trampoline();
-#ifdef CONFIG_FA_DUMP
- /*
- * If we fail to reserve memory for firmware-assisted dump then
- * fallback to kexec based kdump.
- */
- if (fadump_reserve_mem() == 0)
-#endif
- reserve_crashkernel();
early_reserve_mem();
/* Ensure that total memory size is page-aligned. */
@@ -777,6 +769,14 @@ void __init early_init_devtree(void *params)
#endif
mmu_early_init_devtree();
+#ifdef CONFIG_FA_DUMP
+ /*
+ * If we fail to reserve memory for firmware-assisted dump then
+ * fallback to kexec based kdump.
+ */
+ if (fadump_reserve_mem() == 0)
+#endif
+ reserve_crashkernel();
#ifdef CONFIG_PPC_POWERNV
/* Scan and build the list of machine check recoverable ranges */