[U-Boot] [PATCH 2/4] malloc_f: fix broken .config caused by CONFIG_SYS_MALLOC_F

Masahiro Yamada yamada.m at jp.panasonic.com
Thu Feb 19 08:47:26 CET 2015


Since commit b724bd7d6349 (dm: Kconfig: Move CONFIG_SYS_MALLOC_F_LEN
to Kconfig), the ".config" created by the configuration has been
wrong.

For example, the following is a snippet of the ".config" generated
by "make beaver_defconfig":

  --------------->8-----------------
  CONFIG_CC_OPTIMIZE_FOR_SIZE=y
  # CONFIG_SYS_MALLOC_F is not set
  CONFIG_SYS_MALLOC_F_LEN=0x1800
  # CONFIG_EXPERT is not set
  ---------------8<-----------------

CONFIG_SYS_MALLOC_F_LEN is supposed to depend on CONFIG_SYS_MALLOC_F
(see the top level Kconfig), but the ".config" above is not actually
following that dependency.

This is caused by two mistakes of commit b724bd7d6349.

[1] Wrong default value of CONFIG_SYS_MALLOC_F
  CONFIG_SYS_MALLOC_F is a boolean option, but its default value is
  set to 0x400.

[2] Missing "if SYS_MALLOC_F" in the default setting in each Kconfig
  For example, arch/arm/cpu/armv7/tegra-common/Kconfig has the line
  "default 0x1800" for SYS_MALLOC_F_LEN.  It must be described as
  "default 0x1800 if SYS_MALLOC_F" to follow the dependency.

Those two bugs together create such a broken ".config".

Unfortunately, even if we correct both [1] and [2], the value of
CONFIG_SYS_MALLOC_F_LEN is not set as we expect.
The "default 0x1800 if SYS_MALLOC_F" would be simply ignored because
the "default 0x400" in the top level Kconfig is parsed first.

Notice that if multiple default lines appear for the same CONFIG,
the first one takes precedence.

So, this commit correct [1] and [2], also leaves some comments
in arch/arm/cpu/armv7/tegra-common/Kconfig and arch/x86/Kconfig
to notify not-working default values.

If you want to change the default value of CONFIG_SYS_MALLOC_F_LEN,
the easiest way would be to specify it in each *_defconfig.

It is true that describing SoC-common default values in each Kconfig
seems handy, but it often introduces nasty problems.
If you do not understand well how Kconfig works, as you see above,
you could easily create a broken .config file.

The default value 0x400 is redundant for OMAP, Exynos, UniPhier, etc.
They can be simply removed.

There are still redundant "CONFIG_SYS_MALLOC_F_LEN=0x400" in many
defconfig files, but this commit is not touching them.

Signed-off-by: Masahiro Yamada <yamada.m at jp.panasonic.com>
---

 Kconfig                                 | 1 -
 arch/arm/cpu/armv7/exynos/Kconfig       | 3 ---
 arch/arm/cpu/armv7/omap3/Kconfig        | 3 ---
 arch/arm/cpu/armv7/tegra-common/Kconfig | 4 +++-
 arch/arm/cpu/armv7/uniphier/Kconfig     | 3 ---
 arch/x86/Kconfig                        | 4 +++-
 board/amcc/canyonlands/Kconfig          | 4 ----
 board/ti/am335x/Kconfig                 | 3 ---
 8 files changed, 6 insertions(+), 19 deletions(-)

diff --git a/Kconfig b/Kconfig
index 75bab7f..d40f9ec 100644
--- a/Kconfig
+++ b/Kconfig
@@ -58,7 +58,6 @@ config CC_OPTIMIZE_FOR_SIZE
 
 config SYS_MALLOC_F
 	bool "Enable malloc() pool before relocation"
-	default 0x400
 	help
 	  Before relocation memory is very limited on many platforms. Still,
 	  we can provide a small malloc() pool if needed. Driver model in
diff --git a/arch/arm/cpu/armv7/exynos/Kconfig b/arch/arm/cpu/armv7/exynos/Kconfig
index 2064efa..23869ce 100644
--- a/arch/arm/cpu/armv7/exynos/Kconfig
+++ b/arch/arm/cpu/armv7/exynos/Kconfig
@@ -83,9 +83,6 @@ config DM_GPIO
 config SYS_MALLOC_F
 	default y if !SPL_BUILD
 
-config SYS_MALLOC_F_LEN
-	default 0x400 if !SPL_BUILD
-
 source "board/samsung/smdkv310/Kconfig"
 source "board/samsung/trats/Kconfig"
 source "board/samsung/universal_c210/Kconfig"
diff --git a/arch/arm/cpu/armv7/omap3/Kconfig b/arch/arm/cpu/armv7/omap3/Kconfig
index 4644098..2e193ab 100644
--- a/arch/arm/cpu/armv7/omap3/Kconfig
+++ b/arch/arm/cpu/armv7/omap3/Kconfig
@@ -105,9 +105,6 @@ config DM_SERIAL
 config SYS_MALLOC_F
 	default y if DM && !SPL_BUILD
 
-config SYS_MALLOC_F_LEN
-	default 0x400 if DM && !SPL_BUILD
-
 config SYS_SOC
 	default "omap3"
 
diff --git a/arch/arm/cpu/armv7/tegra-common/Kconfig b/arch/arm/cpu/armv7/tegra-common/Kconfig
index ee32469..0de13ae 100644
--- a/arch/arm/cpu/armv7/tegra-common/Kconfig
+++ b/arch/arm/cpu/armv7/tegra-common/Kconfig
@@ -20,8 +20,10 @@ endchoice
 config SYS_MALLOC_F
 	default y
 
+# This is meaningless.
+# "default 0x400" in the top level Kconfig is used in stead.
 config SYS_MALLOC_F_LEN
-	default 0x1800
+	default 0x1800 if SYS_MALLOC_F
 
 config USE_PRIVATE_LIBGCC
 	default y if SPL_BUILD
diff --git a/arch/arm/cpu/armv7/uniphier/Kconfig b/arch/arm/cpu/armv7/uniphier/Kconfig
index 8fdef28..371b274 100644
--- a/arch/arm/cpu/armv7/uniphier/Kconfig
+++ b/arch/arm/cpu/armv7/uniphier/Kconfig
@@ -51,9 +51,6 @@ endchoice
 config SYS_MALLOC_F
 	default y
 
-config SYS_MALLOC_F_LEN
-	default 0x400
-
 config CMD_PINMON
 	bool "Enable boot mode pins monitor command"
 	default y
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 35d24e4..2275374 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -79,8 +79,10 @@ config DM_SERIAL
 config SYS_MALLOC_F
 	default y
 
+# This is meaningless.
+# "default 0x400" in the top level Kconfig is used in stead.
 config SYS_MALLOC_F_LEN
-	default 0x800
+	default 0x800 if SYS_MALLOC_F
 
 config RAMBASE
 	hex
diff --git a/board/amcc/canyonlands/Kconfig b/board/amcc/canyonlands/Kconfig
index 848e08f..c0dbd18 100644
--- a/board/amcc/canyonlands/Kconfig
+++ b/board/amcc/canyonlands/Kconfig
@@ -43,8 +43,4 @@ config SYS_MALLOC_F
 	bool
 	default y
 
-config SYS_MALLOC_F_LEN
-	hex
-	default 0x400
-
 endif
diff --git a/board/ti/am335x/Kconfig b/board/ti/am335x/Kconfig
index a20e0c1..cad10c2 100644
--- a/board/ti/am335x/Kconfig
+++ b/board/ti/am335x/Kconfig
@@ -50,7 +50,4 @@ config DM_SERIAL
 config SYS_MALLOC_F
 	default y if DM && !SPL_BUILD
 
-config SYS_MALLOC_F_LEN
-	default 0x400 if DM && !SPL_BUILD
-
 endif
-- 
1.9.1



More information about the U-Boot mailing list