From: Helge Deller <deller@gmx.de>
Date: Wed, 3 May 2023 16:39:56 +0200
Subject: [PATCH] parisc: Fix argument pointer in real64_call_asm()
References: bsc#1012628
Patch-mainline: 6.3.2
Git-commit: 6e3220ba3323a2c24be834aebf5d6e9f89d0993f
commit 6e3220ba3323a2c24be834aebf5d6e9f89d0993f upstream.
Fix the argument pointer (ap) to point to real-mode memory
instead of virtual memory.
It's interesting that this issue hasn't shown up earlier, as this could
have happened with any 64-bit PDC ROM code.
I just noticed it because I suddenly faced a HPMC while trying to execute
the 64-bit STI ROM code of an Visualize-FXe graphics card for the STI
text console.
Signed-off-by: Helge Deller <deller@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
arch/parisc/kernel/real2.S | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/arch/parisc/kernel/real2.S b/arch/parisc/kernel/real2.S
index 4dc12c4c..509d18b8 100644
--- a/arch/parisc/kernel/real2.S
+++ b/arch/parisc/kernel/real2.S
@@ -235,9 +235,6 @@ ENTRY_CFI(real64_call_asm)
/* save fn */
copy %arg2, %r31
- /* set up the new ap */
- ldo 64(%arg1), %r29
-
/* load up the arg registers from the saved arg area */
/* 32-bit calling convention passes first 4 args in registers */
ldd 0*REG_SZ(%arg1), %arg0 /* note overwriting arg0 */
@@ -249,7 +246,9 @@ ENTRY_CFI(real64_call_asm)
ldd 7*REG_SZ(%arg1), %r19
ldd 1*REG_SZ(%arg1), %arg1 /* do this one last! */
+ /* set up real-mode stack and real-mode ap */
tophys_r1 %sp
+ ldo -16(%sp), %r29 /* Reference param save area */
b,l rfi_virt2real,%r2
nop
--
2.35.3