Date: Fri, 06 Dec 2019 15:21:57 +0000 From: bugzilla-noreply@freebsd.org To: virtualization@FreeBSD.org Subject: [Bug 238095] Current console input freezes in hyperv gen 2 VM after randon amount of time Message-ID: <bug-238095-27103-YQFEpCiKB9@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-238095-27103@https.bugs.freebsd.org/bugzilla/> References: <bug-238095-27103@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D238095 --- Comment #13 from Hans Petter Selasky <hselasky@FreeBSD.org> --- Last time I was debugging something in this area, I found that the UART registers, which appear emulated, have some races. For example if I was rea= ding the UART registers right before posting a doorbell on the mlx4en driver, the hypervisor would reboot the image :-( + if (mlx4_crash !=3D 0) { + while (1) { + inb(0x3f8+5); + } + } + __raw_writel((__force u32)val, + &priv->mfunc.comm->slave_write); I was not able to get to the bottom of this due to lack of interest from the hypervisor developers. This race happens only with N number of CPUs. You may play around with inb() in the network driver code and see if you can provoke a similar action. --HPS --=20 You are receiving this mail because: You are the assignee for the bug.=
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