Re: regression: grass turns red

[Alexander van Heukelum]

Hi Hans,

Could you check if the attached patch solves your problem?

Greetings,
    Alexander van Heukelum

On Sun, Mar 24, 2013, at 22:19, Hans de Bruin wrote:
> commit 49cb25e9290 x86: 'get rid of pt_regs argument in vm86/vm86old' 
> somehow breaks the colors when I play 'civilization I' under xdosemu. 
> During the intro of the game something the colors get messed up. When 
> the game begins the grass of the earth is red. Reverting the  commit 
> fixes the problem.
> 
> -- 
> Hans
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From 2b09f37fd9defc02c6da9900e23418a401d7a2b9 Mon Sep 17 00:00:00 2001
From: Alexander van Heukelum <heukelum@xxxxxxxxxxx>
Date: Tue, 26 Mar 2013 21:57:43 +0100
Subject: [PATCH] x86, vm86: fix VM86 syscalls: use asmlinkage calling convention

This might solve the issue of the red grass in 'civilization I' under xdosemu. Commit
49cb25e9290 x86: 'get rid of pt_regs argument in vm86/vm86old' got rid of the pt_regs
stub for sys_vm86old and sys_vm86. The functions were, however, not changed to use the
asmlinkage calling convention.

Signed-off-by: Alexander van Heukelum <heukelum@xxxxxxxxxxx>
---
 arch/x86/include/asm/syscalls.h | 4 ++--
 arch/x86/kernel/vm86_32.c       | 6 ++++--
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h
index 6cf0a9c..a245b88 100644
--- a/arch/x86/include/asm/syscalls.h
+++ b/arch/x86/include/asm/syscalls.h
@@ -37,8 +37,8 @@ asmlinkage int sys_get_thread_area(struct user_desc __user *);
 unsigned long sys_sigreturn(void);
 
 /* kernel/vm86_32.c */
-int sys_vm86old(struct vm86_struct __user *);
-int sys_vm86(unsigned long, unsigned long);
+asmlinkage int sys_vm86old(struct vm86_struct __user *);
+asmlinkage int sys_vm86(unsigned long, unsigned long);
 
 #else /* CONFIG_X86_32 */
 
diff --git a/arch/x86/kernel/vm86_32.c b/arch/x86/kernel/vm86_32.c
index 1cf5766..7f72807 100644
--- a/arch/x86/kernel/vm86_32.c
+++ b/arch/x86/kernel/vm86_32.c
@@ -202,7 +202,7 @@ out:
 static int do_vm86_irq_handling(int subfunction, int irqnumber);
 static void do_sys_vm86(struct kernel_vm86_struct *info, struct task_struct *tsk);
 
-int sys_vm86old(struct vm86_struct __user *v86)
+asmlinkage int sys_vm86old(struct vm86_struct __user *v86)
 {
 	struct kernel_vm86_struct info; /* declare this _on top_,
 					 * this avoids wasting of stack space.
@@ -227,11 +227,12 @@ int sys_vm86old(struct vm86_struct __user *v86)
 	do_sys_vm86(&info, tsk);
 	ret = 0;	/* we never return here */
 out:
+	asmlinkage_protect(1, ret, v86);
 	return ret;
 }
 
 
-int sys_vm86(unsigned long cmd, unsigned long arg)
+asmlinkage int sys_vm86(unsigned long cmd, unsigned long arg)
 {
 	struct kernel_vm86_struct info; /* declare this _on top_,
 					 * this avoids wasting of stack space.
@@ -278,6 +279,7 @@ int sys_vm86(unsigned long cmd, unsigned long arg)
 	do_sys_vm86(&info, tsk);
 	ret = 0;	/* we never return here */
 out:
+	asmlinkage_protect(2, ret, cmd, arg);
 	return ret;
 }
 
-- 
1.8.1.2