Date: Tue, 15 Mar 2016 15:42:53 +0000 (UTC) From: Konstantin Belousov <kib@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r296908 - in head/sys: amd64/amd64 i386/i386 Message-ID: <201603151542.u2FFgr0f078421@repo.freebsd.org>
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Author: kib Date: Tue Mar 15 15:42:53 2016 New Revision: 296908 URL: https://svnweb.freebsd.org/changeset/base/296908 Log: The PKRU state size is 4 bytes, its support makes the XSAVE area size non-multiple of 64 bytes. Thereafter, the user state save area is misaligned, which triggers assertion in the debugging kernels, or segmentation violation on accesses for non-debugging configs. Force the desired alignment of the user save area as the fix (workaround is to disable bit 9 in the hw.xsave_mask loader tunable). This correction is required for booting on the upcoming Intel' Purley platform. Reported and tested by: "Pieper, Jeffrey E" <jeffrey.e.pieper@intel.com>, jimharris Sponsored by: The FreeBSD Foundation MFC after: 3 days Modified: head/sys/amd64/amd64/vm_machdep.c head/sys/i386/i386/vm_machdep.c Modified: head/sys/amd64/amd64/vm_machdep.c ============================================================================== --- head/sys/amd64/amd64/vm_machdep.c Tue Mar 15 15:31:17 2016 (r296907) +++ head/sys/amd64/amd64/vm_machdep.c Tue Mar 15 15:42:53 2016 (r296908) @@ -102,8 +102,8 @@ get_pcb_user_save_td(struct thread *td) vm_offset_t p; p = td->td_kstack + td->td_kstack_pages * PAGE_SIZE - - cpu_max_ext_state_size; - KASSERT((p % 64) == 0, ("Unaligned pcb_user_save area")); + roundup2(cpu_max_ext_state_size, XSAVE_AREA_ALIGN); + KASSERT((p % XSAVE_AREA_ALIGN) == 0, ("Unaligned pcb_user_save area")); return ((struct savefpu *)p); } @@ -122,7 +122,8 @@ get_pcb_td(struct thread *td) vm_offset_t p; p = td->td_kstack + td->td_kstack_pages * PAGE_SIZE - - cpu_max_ext_state_size - sizeof(struct pcb); + roundup2(cpu_max_ext_state_size, XSAVE_AREA_ALIGN) - + sizeof(struct pcb); return ((struct pcb *)p); } Modified: head/sys/i386/i386/vm_machdep.c ============================================================================== --- head/sys/i386/i386/vm_machdep.c Tue Mar 15 15:31:17 2016 (r296907) +++ head/sys/i386/i386/vm_machdep.c Tue Mar 15 15:42:53 2016 (r296908) @@ -127,8 +127,8 @@ get_pcb_user_save_td(struct thread *td) vm_offset_t p; p = td->td_kstack + td->td_kstack_pages * PAGE_SIZE - - cpu_max_ext_state_size; - KASSERT((p % 64) == 0, ("Unaligned pcb_user_save area")); + roundup2(cpu_max_ext_state_size, XSAVE_AREA_ALIGN); + KASSERT((p % XSAVE_AREA_ALIGN) == 0, ("Unaligned pcb_user_save area")); return ((union savefpu *)p); } @@ -147,7 +147,8 @@ get_pcb_td(struct thread *td) vm_offset_t p; p = td->td_kstack + td->td_kstack_pages * PAGE_SIZE - - cpu_max_ext_state_size - sizeof(struct pcb); + roundup2(cpu_max_ext_state_size, XSAVE_AREA_ALIGN) - + sizeof(struct pcb); return ((struct pcb *)p); }
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