6.6-stable review patch. If anyone has any objections, please let me know.
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From: Sven Schnelle svens@stackframe.org
commit 5fb1d3ce3e74a4530042795e1e065422295f1371 upstream.
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: Sven Schnelle svens@stackframe.org Cc: stable@vger.kernel.org Signed-off-by: Helge Deller deller@gmx.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- arch/parisc/kernel/asm-offsets.c | 2 ++ arch/parisc/kernel/entry.S | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-)
--- a/arch/parisc/kernel/asm-offsets.c +++ b/arch/parisc/kernel/asm-offsets.c @@ -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); --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -1846,6 +1846,10 @@ 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) */ @@ -1859,7 +1863,6 @@ 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.