lkml.org 
[lkml]   [2012]   [Sep]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] tpm: fix tpm_acpi sparse warning on different address spaces
On Thu, Aug 30, 2012 at 02:21:55PM -0500, Kent Yoder wrote:
> On Thu, Aug 30, 2012 at 10:45:56AM -0700, Dan Carpenter wrote:
> > On Thu, Aug 30, 2012 at 09:38:41AM -0500, Kent Yoder wrote:
> > > acpi_os_map_memory expects its return value to be in the __iomem address
> > > space. Cast it back later when used in a memcpy to avoid the same sparse
> > > warning there.
> > >
> > > Signed-off-by: Kent Yoder <key@linux.vnet.ibm.com>
> >
> > I can't download linux-next right now but I don't think this is the
> > correct fix. I don't think you can memcpy() directly from __iomem.
> > The static checker is warning about a valid bug which should be
> > addressed instead of just casted away and silenced.
>
> I took a look at other uses of the return from acpi_os_map_memory(),
> such as acpi_tb_parse_fadt(), which passes the returned pointer to
> acpi_tb_create_local_fadt(), which uses ACPI_MEMCPY on it, which is just
> memcpy. This code lives in drivers/acpi.
>

Sparse finds that bug as well. ;)

drivers/acpi/acpica/tbfadt.c:247:15: warning: incorrect type in assignment (different address spaces)
drivers/acpi/acpica/tbfadt.c:247:15: expected struct acpi_table_header *table
drivers/acpi/acpica/tbfadt.c:247:15: got void [noderef] <asn:2>*
drivers/acpi/acpica/tbfadt.c:266:30: warning: incorrect type in argument 1 (different address spaces)
drivers/acpi/acpica/tbfadt.c:266:30: expected void [noderef] <asn:2>*logical_address
drivers/acpi/acpica/tbfadt.c:266:30: got struct acpi_table_header *table

It should be memcpy_fromio() probably.

regards,
dan carpenter



\
 
 \ /
  Last update: 2012-09-02 19:21    [W:0.056 / U:0.780 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site