d/freebsd-skq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

The PKRU state size is 4 bytes, its support makes the XSAVE area size

Browse Source 
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
This commit is contained in:
kib 2016-03-15 15:42:53 +00:00
parent 41527ba958
commit 3d336a82bd
2 changed files with 8 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
sys/amd64/amd64/vm_machdep.c
View File

@ -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);
}

7
sys/i386/i386/vm_machdep.c
View File

@ -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);
}