lkml.org 
[lkml]   [2017]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
SubjectRE: [PATCH v2] virt: vbox: use %pap format for printing resource_size_t
Date
From: Arnd Bergmann
> Sent: 21 December 2017 16:15
>
> resource_size_t may be larger than pointers depending on configuration,
> so we can run into this build warning:
>
> drivers/virt/vboxguest/vboxguest_linux.c: In function 'vbg_pci_probe':
> drivers/virt/vboxguest/vboxguest_linux.c:295:4: error: cast to pointer from integer of different size
> [-Werror=int-to-pointer-cast]
> drivers/virt/vboxguest/vboxguest_linux.c:367:4: error: cast to pointer from integer of different size
> [-Werror=int-to-pointer-cast]
>
> This uses the special %pap to print the address by reference.
>
> Fixes: 0ba002bc4393 ("virt: Add vboxguest driver for Virtual Box Guest integration")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> v2: Use %pap instead of the %rR that was just as incorrect, as
> pointed out by Joe Perches.
> ---
> drivers/virt/vboxguest/vboxguest_linux.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/virt/vboxguest/vboxguest_linux.c b/drivers/virt/vboxguest/vboxguest_linux.c
> index d045aa51ce03..82e280d38cc2 100644
> --- a/drivers/virt/vboxguest/vboxguest_linux.c
> +++ b/drivers/virt/vboxguest/vboxguest_linux.c
> @@ -291,8 +291,8 @@ static int vbg_pci_probe(struct pci_dev *pci, const struct pci_device_id *id)
>
> vmmdev = devm_ioremap(dev, mmio, mmio_len);
> if (!vmmdev) {
> - vbg_err("vboxguest: Error ioremap failed; MMIO addr=%p size=%d\n",
> - (void *)mmio, (int)mmio_len);
> + vbg_err("vboxguest: Error ioremap failed; MMIO addr=%pap size=%pap\n",
> + &mmio, &mmio_len);

Are you sure about the type of mmio_len?
While the argument to devm_ioremap() is of type resource_size_t it seems
extremely unlikely that the actual value will exceed 2^32.
Using a 64bit type for the length on 32bit systems will generate horrid code.

I can't see the code in my tree to check.

David

\
 
 \ /
  Last update: 2017-12-21 18:02    [W:0.041 / U:0.620 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site