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    SubjectRe: [PATCH 11/22] pci: lto: fix PREL32 relocations
    OK by me, but please update the subject to match convention:

    PCI: Fix PREL32 relocations for LTO

    and include a hint in the commit log about what LTO is. At least
    expand the initialism once. Googling for "LTO" isn't very useful.

    With Clang's Link Time Optimization (LTO), the compiler ... ?

    On Wed, Jun 24, 2020 at 01:31:49PM -0700, Sami Tolvanen wrote:
    > With LTO, the compiler can rename static functions to avoid global
    > naming collisions. As PCI fixup functions are typically static,
    > renaming can break references to them in inline assembly. This
    > change adds a global stub to DECLARE_PCI_FIXUP_SECTION to fix the
    > issue when PREL32 relocations are used.
    >
    > Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

    Acked-by: Bjorn Helgaas <bhelgaas@google.com>

    > ---
    > include/linux/pci.h | 15 ++++++++++-----
    > 1 file changed, 10 insertions(+), 5 deletions(-)
    >
    > diff --git a/include/linux/pci.h b/include/linux/pci.h
    > index c79d83304e52..1e65e16f165a 100644
    > --- a/include/linux/pci.h
    > +++ b/include/linux/pci.h
    > @@ -1909,19 +1909,24 @@ enum pci_fixup_pass {
    > };
    >
    > #ifdef CONFIG_HAVE_ARCH_PREL32_RELOCATIONS
    > -#define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \
    > - class_shift, hook) \
    > - __ADDRESSABLE(hook) \
    > +#define ___DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \
    > + class_shift, hook, stub) \
    > + void stub(struct pci_dev *dev) { hook(dev); } \
    > asm(".section " #sec ", \"a\" \n" \
    > ".balign 16 \n" \
    > ".short " #vendor ", " #device " \n" \
    > ".long " #class ", " #class_shift " \n" \
    > - ".long " #hook " - . \n" \
    > + ".long " #stub " - . \n" \
    > ".previous \n");
    > +
    > +#define __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \
    > + class_shift, hook, stub) \
    > + ___DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \
    > + class_shift, hook, stub)
    > #define DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \
    > class_shift, hook) \
    > __DECLARE_PCI_FIXUP_SECTION(sec, name, vendor, device, class, \
    > - class_shift, hook)
    > + class_shift, hook, __UNIQUE_ID(hook))
    > #else
    > /* Anonymous variables would be nice... */
    > #define DECLARE_PCI_FIXUP_SECTION(section, name, vendor, device, class, \
    > --
    > 2.27.0.212.ge8ba1cc988-goog
    >

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