Date: Thu, 27 May 2021 15:42:02 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 255997] fpu_kern_thread is called before fpu_initialstate has been set in ktls_kern_thread Message-ID: <bug-255997-227-AyHvWrRI0K@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-255997-227@https.bugs.freebsd.org/bugzilla/> References: <bug-255997-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D255997 --- Comment #2 from Henning Zabel <h.zabel@beckhoff.com> --- we are using a modified version of the freebsd kernel. because we do floati= ng point operations within spinlocks a "device not available" exception may br= eak these locks. because of this we avoid using fpu emulation for kernel threads and restore a valid state in fpu_enter and fpu_kern_thread. we also restore= the fpu state within context switches to a kernel thread with FPU_KERN set.=20 this modified kernel will not run, because ktls_kern_thread then tries to restore an uninitialized state. thus, the ktls thread itself is not the problem, but it the first hitting this situation. currently it seems not to be a problem for the freebsd 13 kernel, neverthel= ess its a fault. --=20 You are receiving this mail because: You are the assignee for the bug.=
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