Re: arm64 syzbot instances
From: John Garry <hidden>
Date: 2021-03-15 09:46:02
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On 12/03/2021 10:52, Arnd Bergmann wrote:
On Fri, Mar 12, 2021 at 11:38 AM Dmitry Vyukov [off-list ref] wrote:quoted
On Fri, Mar 12, 2021 at 11:11 AM Arnd Bergmann [off-list ref] wrote: It does not happen too often on syzbot so far, so let's try to do the right thing first. I've filed: https://bugs.launchpad.net/qemu/+bug/1918917 with a link to this thread. To be fair, I don't fully understand what I am talking about, I hope I proxied your description properly.Thanks, looks good. I provided a little more detail in a comment there. Arnd .
From looking at the bug report, my impression is that this is a qemu issue, as the logical IO space is mapped to the PCI host bridge IO space, and qemu does not handle accesses to that CPU addressable region at all. As Arnd said. However, we really should not be accessing logical IO ports 0 or 0x2f8 at all via ttyS3 if not enumerated from PCI device at that logical IO port. That is what I think anyway, as who knows what device - if any - really exists at that location. That is why I had this patch to just stop accesses to legacy IO port regions on arm64: https://lore.kernel.org/lkml/1610729929-188490-2-git-send-email-john.garry@huawei.com/ (local) Thanks, John _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel