From 51175a2a530dfce9528b6bb2e4f29c6ff28efafe Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 15 Oct 2025 23:21:41 +0200 Subject: parisc: entry: set W bit for !compat tasks in syscall_restore_rfi() 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 Cc: stable@vger.kernel.org Signed-off-by: Helge Deller Signed-off-by: Greg Kroah-Hartman --- arch/parisc/kernel/asm-offsets.c | 2 ++ arch/parisc/kernel/entry.S | 5 ++++- 2 files changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/parisc/kernel/asm-offsets.c b/arch/parisc/kernel/asm-offsets.c index 21e900c0aa95..4751872cf20d 100644 --- 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); diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index 7ece269145c8..13e34b06d30c 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -1824,6 +1824,10 @@ 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) */ @@ -1837,7 +1841,6 @@ 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. -- cgit v1.2.3