如何一键优雅的更新内核patch

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一、进入内核，修改内核代码

cd kernel/linux/linux-5.10
vim drivers/Kconfig
# 在倒数第二行加入：source "drivers/tracepoint/Kconfig"

source "drivers/most/Kconfig"

source "drivers/accesstokenid/Kconfig"

source "drivers/tracepoint/Kconfig"
endmenu

二、打patch

patch -p1 < ../patches/linux-5.10/rk3568_patch/kernel.patch

如果想撤回patch方法

patch -Rp1 < ../patches/linux-5.10/rk3568_patch/kernel.patch

三、解决冲突（如果存在）

$ git status | grep rej
Refresh index: 100% (70816/70816), done.
        drivers/Kconfig.rej

上面表示drivers/Kconfig文件的打patch时候有冲突被拒绝了，需要手动进行修改

• 打开drivers/Kconfig.rej文件

  --- drivers/Kconfig
  +++ drivers/Kconfig
  @@ -239,4 +239,8 @@ source "drivers/counter/Kconfig"
   source "drivers/most/Kconfig"
  
   source "drivers/accesstokenid/Kconfig"
  +
  +source "drivers/rkflash/Kconfig"
  +
  +source "drivers/rk_nand/Kconfig"
   endmenu

  这个文件的意思是需要在source "drivers/accesstokenid/Kconfig"的下面添加四行内容

• 打开drivers/Kconfig文件，手动解决patch添加

  # 修改前
  source "drivers/most/Kconfig"
  
  source "drivers/accesstokenid/Kconfig"
  
  source "drivers/tracepoint/Kconfig"
  endmenu
  
  # 修改后
  source "drivers/most/Kconfig"
  
  source "drivers/accesstokenid/Kconfig"
  
  source "drivers/tracepoint/Kconfig"
  
  source "drivers/rkflash/Kconfig"
  
  source "drivers/rk_nand/Kconfig"
  endmenu

• 删除冲突生成的临时orig和rej文件

  rm -rf drivers/Kconfig.orig drivers/Kconfig.rej

• 至此冲突解决完

四、生成新的patch

git生成patch和打patch

git add .
git commit . -m"add tracepoint"
# 如果只有一次提交使用format-patch方便
git format-patch HEAD^
# 如果想打commit1和commit2之间的patch
# 其中commit1是起始的commit; commit2是结束的commit
git diff commit1 commit2 > demo.patch

此时会生成一个patch文件0001-add-tracepoint.patch

五、原patch修改

我们比对0001-add-tracepoint.patch 和 ../patches/linux-5.10/rk3568_patch/kernel.patch文件发现差异特别大，那是因为每次生成的patch时候对应的文件顺序是不一样的，所以差异比较大，我们要做的是将我们修改的文件patch内容替换即可。

# 比较文件的方法
diff 0001-add-tracepoint.patch ../patches/linux-5.10/rk3568_patch/kernel.patch

打开0001-add-tracepoint.patch文件搜索drivers/Kconfig，将如下内容替换掉../patches/linux-5.10/rk3568_patch/kernel.patch中的相同位置内容，至此，patch修改完成

# 0001-add-tracepoint.patch中的内容
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 826b2b19d..5720a24fb 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -239,4 +239,10 @@ source "drivers/counter/Kconfig"
 source "drivers/most/Kconfig"

 source "drivers/accesstokenid/Kconfig"
+
+source "drivers/tracepoint/Kconfig"
+
+source "drivers/rkflash/Kconfig"
+
+source "drivers/rk_nand/Kconfig"
 endmenu

# 原../patches/linux-5.10/rk3568_patch/kernel.patch中的内容
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 826b2b19d..d7f2fc98b 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -239,4 +239,8 @@ source "drivers/counter/Kconfig"
 source "drivers/most/Kconfig"

 source "drivers/accesstokenid/Kconfig"
+
+source "drivers/rkflash/Kconfig"
+
+source "drivers/rk_nand/Kconfig"
 endmenu

# 替换后../patches/linux-5.10/rk3568_patch/kernel.patch中的内容
diff --git a/drivers/Kconfig b/drivers/Kconfig
index 826b2b19d..5720a24fb 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -239,4 +239,10 @@ source "drivers/counter/Kconfig"
 source "drivers/most/Kconfig"

 source "drivers/accesstokenid/Kconfig"
+
+source "drivers/tracepoint/Kconfig"
+
+source "drivers/rkflash/Kconfig"
+
+source "drivers/rk_nand/Kconfig"
 endmenu

六、内核版本回退

rm 0001-add-tracepoint.patch
git reset --hard HEAD^

七、至此kernel.patch修改完成