Re: [PATCH 1/1] PCI: fix on-stack pci_device_id's

From: Fengguang Wu
Date: Mon Sep 10 2012 - 18:55:26 EST


On Mon, Sep 10, 2012 at 02:44:32PM -0600, Bjorn Helgaas wrote:
> On Mon, Sep 10, 2012 at 1:36 PM, Jiri Slaby <jslaby@xxxxxxx> wrote:
> > Commit "PCI: Use pci_device_id on stack for pci_get_subsys/class() to
> > avoid kmalloc" changed heap allocations to on-stack variables, but it
> > did not add initialization of other than set members. This causes
> > random failures during bootup wherever pci device is needed to be
> > found. Hence the boot just hangs or panics.
> >
> > This patches fixes it by setting the content of pci_device_id directly
> > in the initializer.
>
> Nice! I fixed this already by adding a memset(), but I like your way
> better. I knew we could initialize members of a structure on the
> stack, but I didn't know C guaranteed that uninitialized members would
> be implicitly initialized also. But apparently it does:
>
> http://stackoverflow.com/questions/10828294/c-and-c-partial-initialization-of-automatic-structure

Signed-off-by: Fengguang Wu <fengguang.wu@xxxxxxxxx>

For the record, I proposed the same initializer-style fix in the very
beginning that you didn't realize its beauty until now ;-)

Thanks,
Fengguang
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