Date: Sat, 10 Apr 2021 20:31:12 +0000 From: bugzilla-noreply@freebsd.org To: virtualization@FreeBSD.org Subject: [Bug 254956] Assertion fails when passing-through PCI device with large memory BAR Message-ID: <bug-254956-27103@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=254956 Bug ID: 254956 Summary: Assertion fails when passing-through PCI device with large memory BAR Product: Base System Version: 13.0-STABLE Hardware: amd64 OS: Any Status: New Severity: Affects Some People Priority: --- Component: bhyve Assignee: virtualization@FreeBSD.org Reporter: crowston@protonmail.com Passing-through a PCI device with a large BAR (for instance, a GPU) fails when the 0xfff... probe address is assigned to the BAR: bhyve exists with an assertion failed such as Assertion failed: (error == 0), function modify_bar_registration, file /usr/src/usr.sbin/bhyve/pci_emul.c, line 501. During boot the system assigns the BAR a temporary address such that addr + size = 0xffffffff. It immediately restores the previous address. This is not a problem for most PCI devices. However, when passing through a GPU, the temporary memory region is large enough to occupy space already taken by the high performance time counter. This causes the assertion to fail at run time. I propose that when a probing address such as this is assigned to the BAR, we do not attempt to intercept it at all. My proposal is here: https://reviews.freebsd.org/D29698 -- You are receiving this mail because: You are the assignee for the bug.help
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