Date: Fri, 27 Sep 2013 06:56:58 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r255905 - stable/9/sys/amd64/amd64 Message-ID: <201309270656.r8R6uwDb089723@svn.freebsd.org>
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Author: kib Date: Fri Sep 27 06:56:58 2013 New Revision: 255905 URL: http://svnweb.freebsd.org/changeset/base/255905 Log: MFC r255844: Ensure that the ERESTART return from the syscall reloads the registers, to make the restarted syscall instruction pass the correct arguments. PR: kern/182161 Modified: stable/9/sys/amd64/amd64/vm_machdep.c Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/amd64/amd64/vm_machdep.c ============================================================================== --- stable/9/sys/amd64/amd64/vm_machdep.c Thu Sep 26 22:47:02 2013 (r255904) +++ stable/9/sys/amd64/amd64/vm_machdep.c Fri Sep 27 06:56:58 2013 (r255905) @@ -400,9 +400,13 @@ cpu_set_syscall_retval(struct thread *td * for the next iteration. * %r10 restore is only required for freebsd/amd64 processes, * but shall be innocent for any ia32 ABI. + * + * Require full context restore to get the arguments + * in the registers reloaded at return to usermode. */ td->td_frame->tf_rip -= td->td_frame->tf_err; td->td_frame->tf_r10 = td->td_frame->tf_rcx; + set_pcb_flags(td->td_pcb, PCB_FULL_IRET); break; case EJUSTRETURN:
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