On Wed, Sep 16, 2020 at 12:06:58PM +0100, Lorenzo Pieralisi wrote: > For arches that do not select CONFIG_GENERIC_IOMAP, the current > pci_iounmap() function does nothing causing obvious memory leaks > for mapped regions that are backed by MMIO physical space. > > In order to detect if a mapped pointer is IO vs MMIO, a check must made > available to the pci_iounmap() function so that it can actually detect > whether the pointer has to be unmapped. > > In configurations where CONFIG_HAS_IOPORT_MAP && !CONFIG_GENERIC_IOMAP, > a mapped port is detected using an ioport_map() stub defined in > asm-generic/io.h. > > Use the same logic to implement a stub (ie __pci_ioport_unmap()) that > detects if the passed in pointer in pci_iounmap() is IO vs MMIO to > iounmap conditionally and call it in pci_iounmap() fixing the issue. > > Leave __pci_ioport_unmap() as a NOP for all other config options. > > Reported-by: George Cherian <george.cherian@xxxxxxxxxxx> > Link: https://lore.kernel.org/lkml/20200905024811.74701-1-yangyingliang@xxxxxxxxxx > Link: https://lore.kernel.org/lkml/20200824132046.3114383-1-george.cherian@xxxxxxxxxxx > Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx> > Cc: Arnd Bergmann <arnd@xxxxxxxx> > Cc: George Cherian <george.cherian@xxxxxxxxxxx> > Cc: Will Deacon <will@xxxxxxxxxx> > Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > Cc: Catalin Marinas <catalin.marinas@xxxxxxx> > Cc: Yang Yingliang <yangyingliang@xxxxxxxxxx> > --- > include/asm-generic/io.h | 39 +++++++++++++++++++++++++++------------ > 1 file changed, 27 insertions(+), 12 deletions(-) This works for me. The only question I have is whether pci_iomap.h is better than io.h for __pci_ioport_unmap(). These headers are really confusing. Either way: Reviewed-by: Catalin Marinas <catalin.marinas@xxxxxxx>
