Date: Thu, 7 Nov 2019 21:14:59 +0000 (UTC) From: Andriy Gapon <avg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r354482 - head/sys/x86/x86 Message-ID: <201911072114.xA7LExVP090362@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: avg Date: Thu Nov 7 21:14:59 2019 New Revision: 354482 URL: https://svnweb.freebsd.org/changeset/base/354482 Log: IPI_TRACE is not really supported on xen x86 stack_save_td_running() can work safely only if IPI_TRACE is a non-maskable interrupt. But at the moment FreeBSD/Xen does not provide support for the NMI delivery mode. So, mark the functionality as unsupported similarly to other platforms without NMI. Maybe there is a way to provide a Xen-specific working stack_save_td_running(), but I couldn't figure it out. MFC after: 3 weeks Sponsored by: Panzura Modified: head/sys/x86/x86/stack_machdep.c Modified: head/sys/x86/x86/stack_machdep.c ============================================================================== --- head/sys/x86/x86/stack_machdep.c Thu Nov 7 21:08:49 2019 (r354481) +++ head/sys/x86/x86/stack_machdep.c Thu Nov 7 21:14:59 2019 (r354482) @@ -135,6 +135,13 @@ int stack_save_td_running(struct stack *st, struct thread *td) { +#ifdef XENHVM + /* + * There is no NMI support on Xen, so this code can lead to + * an inter-processor deadlock. + */ + return (EOPNOTSUPP); +#endif /* XENHVM */ #ifdef STACK THREAD_LOCK_ASSERT(td, MA_OWNED); MPASS(TD_IS_RUNNING(td));
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?201911072114.xA7LExVP090362>