[PATCH 1/3] mm, x86: Fix warning in ioremap RAM check

Toshi Kani
2015-06-19T21:44:57Z

__ioremap_caller() calls __ioremap_check_ram() through
walk_system_ram_range() to check if a target range is RAM.
__ioremap_check_ram() has WARN_ONCE() in a wrong place that
it warns when the given range is not RAM. This misplaced
warning is not exposed since walk_system_ram_range() only
calls __ioremap_check_ram() for RAM ranges.

Move the WARN_ONCE() to the error path of __ioremap_caller(),
and update the message to include the address range.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
---
arch/x86/mm/ioremap.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 70e7444..56f8af7 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -60,8 +60,6 @@ static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages,
!PageReserved(pfn_to_page(start_pfn + i)))
return 1;

- WARN_ONCE(1, "ioremap on RAM pfn 0x%lx\n", start_pfn);
-
return 0;
}

@@ -128,8 +126,11 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
pfn = phys_addr >> PAGE_SHIFT;
last_pfn = last_addr >> PAGE_SHIFT;
if (walk_system_ram_range(pfn, last_pfn - pfn + 1, NULL,
- __ioremap_check_ram) == 1)
+ __ioremap_check_ram) == 1) {
+ WARN_ONCE(1, "ioremap on RAM at 0x%llx - 0x%llx\n",
+ phys_addr, last_addr);
return NULL;
+ }
}
/*
* Mappings have to be page-aligned