Date: Fri, 19 Dec 2014 09:42:41 +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: r275934 - stable/9/sys/amd64/amd64 Message-ID: <201412190942.sBJ9gfUb041620@svn.freebsd.org>
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Author: kib Date: Fri Dec 19 09:42:40 2014 New Revision: 275934 URL: https://svnweb.freebsd.org/changeset/base/275934 Log: MFC r275833: The iret instruction may generate #np and #ss fault, besides #gp. When returning to usermode, the handler for that exceptions is also executed with wrong gs base. Handle all three possible faults in the same way, checking for iret fault, and performing full iret. Modified: stable/9/sys/amd64/amd64/exception.S Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/amd64/amd64/exception.S ============================================================================== --- stable/9/sys/amd64/amd64/exception.S Fri Dec 19 09:36:59 2014 (r275933) +++ stable/9/sys/amd64/amd64/exception.S Fri Dec 19 09:42:40 2014 (r275934) @@ -154,9 +154,13 @@ IDTVEC(xmm) IDTVEC(tss) TRAP_ERR(T_TSSFLT) IDTVEC(missing) - TRAP_ERR(T_SEGNPFLT) + subq $TF_ERR,%rsp + movl $T_SEGNPFLT,TF_TRAPNO(%rsp) + jmp prot_addrf IDTVEC(stk) - TRAP_ERR(T_STKFLT) + subq $TF_ERR,%rsp + movl $T_STKFLT,TF_TRAPNO(%rsp) + jmp prot_addrf IDTVEC(align) TRAP_ERR(T_ALIGNFLT) @@ -319,6 +323,7 @@ IDTVEC(page) IDTVEC(prot) subq $TF_ERR,%rsp movl $T_PROTFLT,TF_TRAPNO(%rsp) +prot_addrf: movq $0,TF_ADDR(%rsp) movq %rdi,TF_RDI(%rsp) /* free up a GP register */ leaq doreti_iret(%rip),%rdi
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