Skip to content

Commit

Permalink
ioremap: Delay sanity check until after a successful mapping
Browse files Browse the repository at this point in the history
While tracking down the reason for an ioremap() failure I was
distracted  by the WARN_ONCE() in __ioremap_caller().

Performing a WARN_ONCE() sanity check before the mapping
is successful seems pointless if the caller sends bad values.

A case in point is when the BIOS provides erroneous screen_info
values causing vesafb_probe() to request an outrageuous size.
The WARN_ONCE is then wasted on bogosity. Move the warning to a
point where the mapping has been successfully allocated.

Addresses:

  http://bugs.launchpad.net/bugs/772042

Reviewed-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Link: http://lkml.kernel.org/r/4DB99D2E.9080106@canonical.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
  • Loading branch information
Tim Gardner authored and Ingo Molnar committed Apr 29, 2011
1 parent 64d21fc commit c7a7b81
Showing 1 changed file with 7 additions and 7 deletions.
14 changes: 7 additions & 7 deletions arch/x86/mm/ioremap.c
Original file line number Diff line number Diff line change
Expand Up @@ -90,13 +90,6 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
if (is_ISA_range(phys_addr, last_addr))
return (__force void __iomem *)phys_to_virt(phys_addr);

/*
* Check if the request spans more than any BAR in the iomem resource
* tree.
*/
WARN_ONCE(iomem_map_sanity_check(phys_addr, size),
KERN_INFO "Info: mapping multiple BARs. Your kernel is fine.");

/*
* Don't allow anybody to remap normal RAM that we're using..
*/
Expand Down Expand Up @@ -170,6 +163,13 @@ static void __iomem *__ioremap_caller(resource_size_t phys_addr,
ret_addr = (void __iomem *) (vaddr + offset);
mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr);

/*
* Check if the request spans more than any BAR in the iomem resource
* tree.
*/
WARN_ONCE(iomem_map_sanity_check(unaligned_phys_addr, unaligned_size),
KERN_INFO "Info: mapping multiple BARs. Your kernel is fine.");

return ret_addr;
err_free_area:
free_vm_area(area);
Expand Down

0 comments on commit c7a7b81

Please sign in to comment.