The patch below was submitted to be applied to the 4.20-stable tree.
I fail to see how this patch meets the stable kernel rules as found at
Documentation/process/stable-kernel-rules.rst.
I could be totally wrong, and if so, please respond to
<stable@xxxxxxxxxxxxxxx> and let me know why this patch should be
applied. Otherwise, it is now dropped from my patch queues, never to be
seen again.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 493a2f812446e92bcb1e69a77381b4d39808d730 Mon Sep 17 00:00:00 2001
From: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
Date: Thu, 14 Feb 2019 18:07:45 +0300
Subject: [PATCH] ARC: enable uboot support unconditionally
After reworking U-boot args handling code and adding paranoid
arguments check we can eliminate CONFIG_ARC_UBOOT_SUPPORT and
enable uboot support unconditionally.
For JTAG case we can assume that core registers will come up
reset value of 0 or in worst case we rely on user passing
'-on=clear_regs' to Metaware debugger.
Cc: stable@xxxxxxxxxxxxxxx
Tested-by: Corentin LABBE <clabbe@xxxxxxxxxxxx>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@xxxxxxxxxxxx>
Signed-off-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 7215f52b3413..d750b302d5ab 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -191,7 +191,6 @@ config NR_CPUS
config ARC_SMP_HALT_ON_RESET
bool "Enable Halt-on-reset boot mode"
- default y if ARC_UBOOT_SUPPORT
help
In SMP configuration cores can be configured as Halt-on-reset
or they could all start at same time. For Halt-on-reset, non
@@ -523,17 +522,6 @@ config ARC_DBG_TLB_PARANOIA
endif
-config ARC_UBOOT_SUPPORT
- bool "Support uboot arg Handling"
- help
- ARC Linux by default checks for uboot provided args as pointers to
- external cmdline or DTB. This however breaks in absence of uboot,
- when booting from Metaware debugger directly, as the registers are
- not zeroed out on reset by mdb and/or ARCv2 based cores. The bogus
- registers look like uboot args to kernel which then chokes.
- So only enable the uboot arg checking/processing if users are sure
- of uboot being in play.
-
config ARC_BUILTIN_DTB_NAME
string "Built in DTB"
help
diff --git a/arch/arc/configs/nps_defconfig b/arch/arc/configs/nps_defconfig
index 6e84060e7c90..621f59407d76 100644
--- a/arch/arc/configs/nps_defconfig
+++ b/arch/arc/configs/nps_defconfig
@@ -31,7 +31,6 @@ CONFIG_ARC_CACHE_LINE_SHIFT=5
# CONFIG_ARC_HAS_LLSC is not set
CONFIG_ARC_KVADDR_SIZE=402
CONFIG_ARC_EMUL_UNALIGNED=y
-CONFIG_ARC_UBOOT_SUPPORT=y
CONFIG_PREEMPT=y
CONFIG_NET=y
CONFIG_UNIX=y
diff --git a/arch/arc/configs/vdk_hs38_defconfig b/arch/arc/configs/vdk_hs38_defconfig
index 1e59a2e9c602..e447ace6fa1c 100644
--- a/arch/arc/configs/vdk_hs38_defconfig
+++ b/arch/arc/configs/vdk_hs38_defconfig
@@ -13,7 +13,6 @@ CONFIG_PARTITION_ADVANCED=y
CONFIG_ARC_PLAT_AXS10X=y
CONFIG_AXS103=y
CONFIG_ISA_ARCV2=y
-CONFIG_ARC_UBOOT_SUPPORT=y
CONFIG_ARC_BUILTIN_DTB_NAME="vdk_hs38"
CONFIG_PREEMPT=y
CONFIG_NET=y
diff --git a/arch/arc/configs/vdk_hs38_smp_defconfig b/arch/arc/configs/vdk_hs38_smp_defconfig
index b5c3f6c54b03..c82cdb10aaf4 100644
--- a/arch/arc/configs/vdk_hs38_smp_defconfig
+++ b/arch/arc/configs/vdk_hs38_smp_defconfig
@@ -15,8 +15,6 @@ CONFIG_AXS103=y
CONFIG_ISA_ARCV2=y
CONFIG_SMP=y
# CONFIG_ARC_TIMERS_64BIT is not set
-# CONFIG_ARC_SMP_HALT_ON_RESET is not set
-CONFIG_ARC_UBOOT_SUPPORT=y
CONFIG_ARC_BUILTIN_DTB_NAME="vdk_hs38_smp"
CONFIG_PREEMPT=y
CONFIG_NET=y
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
index 1f945d0f40da..30e090625916 100644
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -100,7 +100,6 @@ ENTRY(stext)
st.ab 0, [r5, 4]
1:
-#ifdef CONFIG_ARC_UBOOT_SUPPORT
; Uboot - kernel ABI
; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2
; r1 = magic number (always zero as of now)
@@ -108,7 +107,6 @@ ENTRY(stext)
; These are handled later in handle_uboot_args()
st r0, [@uboot_tag]
st r2, [@uboot_arg]
-#endif
; setup "current" tsk and optionally cache it in dedicated r25
mov r9, @init_task
diff --git a/arch/arc/kernel/setup.c b/arch/arc/kernel/setup.c
index 8bb156164556..93d4d6639873 100644
--- a/arch/arc/kernel/setup.c
+++ b/arch/arc/kernel/setup.c
@@ -487,7 +487,6 @@ void __init handle_uboot_args(void)
bool use_embedded_dtb = true;
bool append_cmdline = false;
-#ifdef CONFIG_ARC_UBOOT_SUPPORT
/* check that we know this tag */
if (uboot_tag != UBOOT_TAG_NONE &&
uboot_tag != UBOOT_TAG_CMDLINE &&
@@ -514,7 +513,6 @@ void __init handle_uboot_args(void)
append_cmdline = true;
ignore_uboot_args:
-#endif
if (use_embedded_dtb) {
machine_desc = setup_machine_fdt(__dtb_start);
