Commit 5fb1d3ce authored by Sven Schnelle's avatar Sven Schnelle Committed by Helge Deller
Browse files

parisc: entry: set W bit for !compat tasks in syscall_restore_rfi() 



When the kernel leaves to userspace via syscall_restore_rfi(), the
W bit is not set in the new PSW. This doesn't cause any problems
because there's no 64 bit userspace for parisc. Simple static binaries
are usually loaded at addresses way below the 32 bit limit so the W bit
doesn't matter.

Fix this by setting the W bit when TIF_32BIT is not set.

Signed-off-by: default avatarSven Schnelle <svens@stackframe.org>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarHelge Deller <deller@gmx.de>
parent 3631b9cb

arch/parisc/kernel/asm-offsets.c

+2 −0
Original line number Diff line number Diff line
@@ -258,6 +258,8 @@ int main(void) 
	BLANK();

	DEFINE(TIF_BLOCKSTEP_PA_BIT, 31-TIF_BLOCKSTEP);

	DEFINE(TIF_SINGLESTEP_PA_BIT, 31-TIF_SINGLESTEP);

	DEFINE(TIF_32BIT_PA_BIT, 31-TIF_32BIT);



	BLANK();

	DEFINE(ASM_PMD_SHIFT, PMD_SHIFT);

	DEFINE(ASM_PGDIR_SHIFT, PGDIR_SHIFT);

arch/parisc/kernel/entry.S

+4 −1
Original line number Diff line number Diff line
@@ -1841,6 +1841,10 @@ syscall_restore_rfi: 
	extru,= %r19,TIF_BLOCKSTEP_PA_BIT,1,%r0

	depi	-1,7,1,%r20			   /* T bit */



#ifdef CONFIG_64BIT

	extru,<> %r19,TIF_32BIT_PA_BIT,1,%r0

	depi	-1,4,1,%r20			   /* W bit */

#endif

	STREG	%r20,TASK_PT_PSW(%r1)



	/* Always store space registers, since sr3 can be changed (e.g. fork) */
@@ -1854,7 +1858,6 @@ syscall_restore_rfi: 
	STREG   %r25,TASK_PT_IASQ0(%r1)

	STREG   %r25,TASK_PT_IASQ1(%r1)



	/* XXX W bit??? */

	/* Now if old D bit is clear, it means we didn't save all registers

	 * on syscall entry, so do that now.  This only happens on TRACEME

	 * calls, or if someone attached to us while we were on a syscall.