From: Minep <zelong56@gmail.com>
Date: Sat, 17 Sep 2022 18:10:33 +0000 (+0100)
Subject: fix: load x87 fpu default settings
X-Git-Url: https://scm.lunaixsky.com/lunaix-os.git/commitdiff_plain/d96f52f65ecb90e26be9bd709fbdb1de54795db1?ds=sidebyside

fix: load x87 fpu default settings
fix: forked child should inherit parent's x87 and mmx state
---

diff --git a/lunaix-os/kernel/k_init.c b/lunaix-os/kernel/k_init.c
index fe9cf90..ce4ac6a 100644
--- a/lunaix-os/kernel/k_init.c
+++ b/lunaix-os/kernel/k_init.c
@@ -164,6 +164,11 @@ spawn_proc0()
                  : "i"(KSTACK_TOP), "i"(KCODE_SEG), "r"(proc0->intr_ctx.eip)
                  : "%ebx", "memory");
 
+    // 加载x87默认配置
+    asm volatile("fninit\n"
+                 "fxsave (%%eax)" ::"a"(proc0->fxstate)
+                 : "memory");
+
     // 向调度器注册进程。
     commit_process(proc0);
 
diff --git a/lunaix-os/kernel/process/process.c b/lunaix-os/kernel/process/process.c
index 82f1ffa..74c9380 100644
--- a/lunaix-os/kernel/process/process.c
+++ b/lunaix-os/kernel/process/process.c
@@ -196,6 +196,8 @@ dup_proc()
     pcb->intr_ctx = __current->intr_ctx;
     pcb->parent = __current;
 
+    memcpy(pcb->fxstate, __current->fxstate, 512);
+
     if (__current->cwd) {
         pcb->cwd = __current->cwd;
         vfs_ref_dnode(pcb->cwd);