Re: [PATCH v2 0/6] Fixes for HiSilicon LPC driver and logical PIO code
From: Wei Xu
Date: Tue Jun 25 2019 - 05:57:48 EST
Hi John,
On 6/24/2019 3:35 PM, John Garry wrote:
> As reported in [1], the hisi-lpc driver has certain issues in handling
> logical PIO regions, specifically unregistering regions.
>
> This series add a method to unregister a logical PIO region, and fixes up
> the driver to use them.
>
> RCU usage in logical PIO code looks to always have been broken, so that
> is fixed also. This is not a major fix as the list which RCU protects
> would be rarely modified.
>
> There is another patch to simplify logical PIO registration, made possible
> by the fixes.
>
> At this point, there are still separate ongoing discussions about how to
> stop the logical PIO and PCI host bridge code leaking ranges, as in [2].
>
> Hopefully this series can go through the arm soc tree and the maintainers
> have no issue with that. I'm talking specifically about the logical PIO
> code, which went through PCI tree on only previous upstreaming.
Thanks!
Series applied to the hisilicon fix tree.
But I am not sure it is proper for me to apply and send the pull request
for this patch set.
I will give it a try.
Best Regards,
Wei
>
> Cc. linux-pci@xxxxxxxxxxxxxxx
>
> [1] https://lore.kernel.org/lkml/1560770148-57960-1-git-send-email-john.garry@xxxxxxxxxx/
> [2] https://lore.kernel.org/lkml/4b24fd36-e716-7c5e-31cc-13da727802e7@xxxxxxxxxx/
>
> Changes since v1:
> - Add more reasoning in RCU fix patch
> - Create separate patch to change LOGIC_PIO_CPU_MMIO registration to
> accomodate unregistration
>
> John Garry (6):
> lib: logic_pio: Fix RCU usage
> lib: logic_pio: Avoid possible overlap for unregistering regions
> lib: logic_pio: Add logic_pio_unregister_range()
> bus: hisi_lpc: Unregister logical PIO range to avoid potential
> use-after-free
> bus: hisi_lpc: Add .remove method to avoid driver unbind crash
> lib: logic_pio: Enforce LOGIC_PIO_INDIRECT region ops are set at
> registration
>
> drivers/bus/hisi_lpc.c | 43 +++++++++++++++++---
> include/linux/logic_pio.h | 1 +
> lib/logic_pio.c | 86 +++++++++++++++++++++++++++------------
> 3 files changed, 99 insertions(+), 31 deletions(-)
>