[PATCH v2 01/25] mm, x86: Fix warning in ioremap RAM check

[Dan Williams]

From: Toshi Kani <toshi.kani at hp.com>

__ioremap_caller() calls __ioremap_check_ram() through
walk_system_ram_range() to check if a target range is in RAM.
__ioremap_check_ram() has WARN_ONCE() in a wrong place where 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 __ioremap_caller(), and update the message to
include the address range.

Signed-off-by: Toshi Kani <toshi.kani at hp.com>
Cc: Roland Dreier <roland at purestorage.com>
Cc: Luis R. Rodriguez <mcgrof at suse.com>
Cc: Thomas Gleixner <tglx at linutronix.de>
Cc: H. Peter Anvin <hpa at zytor.com>
Cc: Ingo Molnar <mingo at redhat.com>
Cc: Borislav Petkov <bp at alien8.de>
[djbw: fix format specifier warnings]
Reported-by: kbuild test robot <fengguang.wu at intel.com>
Signed-off-by: Dan Williams <dan.j.williams at intel.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 cc5ccc415cc0..c13f7fdca142 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -63,8 +63,6 @@ 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;
 }
 
@@ -131,8 +129,11 @@ 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 %pa - %pa\n",
+					&phys_addr, &last_addr);
 			return NULL;
+		}
 	}
 	/*
 	 * Mappings have to be page-aligned