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@vger.kernel.org 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@synopsys.com 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@vger.kernel.org Tested-by: Corentin LABBE clabbe@baylibre.com Signed-off-by: Eugeniy Paltsev Eugeniy.Paltsev@synopsys.com Signed-off-by: Vineet Gupta vgupta@synopsys.com
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);