From 1c9cf9b211030a454a84cbc1cb15b82d9aa49011 Mon Sep 17 00:00:00 2001
From: Toshi Kani <toshi.kani@hp.com>
Date: Thu, 16 Jul 2015 17:23:14 -0600
Subject: [PATCH] x86/mm: Move warning from __ioremap_check_ram() to the call
site
__ioremap_check_ram() has a WARN_ONCE() which is emitted when the
given pfn range is not RAM. The warning is bogus in two aspects:
- it never triggers since walk_system_ram_range() only calls
__ioremap_check_ram() for RAM ranges.
- the warning message is wrong as it says: "ioremap on RAM' after it
established that the pfn range is not RAM.
Move the WARN_ONCE() to __ioremap_caller(), and update the message to
include the address range so we get an actual warning when something
tries to ioremap system RAM.
[ tglx: Massaged changelog ]
Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Luis R. Rodriguez <mcgrof@suse.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1437088996-28511-2-git-send-email-toshi.kani@hp.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
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..fd3df0ddb4d4 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 0x%llx - 0x%llx\n",
+ phys_addr, last_addr);
return NULL;
+ }
}
/*
* Mappings have to be page-aligned
--
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