diff options
Diffstat (limited to 'arch/mips/mips-Kconfig-add-QEMUMIPS64-option.patch')
| -rw-r--r-- | arch/mips/mips-Kconfig-add-QEMUMIPS64-option.patch | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/mips/mips-Kconfig-add-QEMUMIPS64-option.patch b/arch/mips/mips-Kconfig-add-QEMUMIPS64-option.patch new file mode 100644 index 00000000..1c1d9408 --- /dev/null +++ b/arch/mips/mips-Kconfig-add-QEMUMIPS64-option.patch @@ -0,0 +1,90 @@ +From 63911f5a1a7753ef0fb2a1b82fa268d7e13c3935 Mon Sep 17 00:00:00 2001 +From: Bruce Ashfield <bruce.ashfield@gmail.com> +Date: Tue, 7 Jan 2020 03:34:12 +0000 +Subject: [PATCH] mips: Kconfig: add QEMUMIPS64 option + +In 5.4+ mips has switched to using the generic VDSO implementation, in +particular the following commits are the bulk of the changes: + + 932bb934ed4d mips: compat: vdso: Use legacy syscalls as fallback + cdab7e2c73d5 mips: vdso: Fix flip/flop vdso building bug + b4c0f7fa5308 mips: vdso: Fix source path + 1f66c45db330 mips: Add clock_gettime64 entry point + abed3d826f2f mips: Add clock_getres entry point + 6393e6064486 mips: fix vdso32 build, again + 24640f233b46 mips: Add support for generic vDSO + 8919975b6171 MIPS: VDSO: Fix build for binutils < 2.25 + 90800281e761 MIPS: VDSO: Remove unused gettimeofday.c + +There is a (currently) unknown interaction between qemumips64, the +mti_malta64 platform, glibc and VDSO that causes a segfault when +gettimeofday is called during boot. It appears that the VDSO +configuration of the gic address is incorrect, and hence when +read_gic_count() is called during do_hres() initialization, the +page is not properly mapped and a segfault is triggered. + +If we avoid reading the gic, and let the vdso syscall fallbacks +be enabled, we are find for boot. The most flexible way to avoid +these reads is to make the two malta clocksources not be selected +when we are booting under qemumips64. This allows other platforms +to not be impacted. + +Once a root cause of this bad mapping is found, we can drop the +new CONFIG_QEMUMIPS64 option and behaviour will revert to using +the git automatically. + +Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com> +--- + arch/mips/Kconfig | 12 ++++++++---- + 1 file changed, 8 insertions(+), 4 deletions(-) + +diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig +index d89efba3d8a4..bc0d3e1cf297 100644 +--- a/arch/mips/Kconfig ++++ b/arch/mips/Kconfig +@@ -118,6 +118,10 @@ config MACH_INGENIC + select CPU_SUPPORTS_CPUFREQ + select MIPS_EXTERNAL_TIMER + ++config QEMUMIPS64 ++ bool "Enable for qemumips64 specific configurations" ++ default n ++ + menu "Machine selection" + + choice +@@ -131,17 +135,17 @@ config MIPS_GENERIC_KERNEL + select BOOT_RAW + select BUILTIN_DTB + select CEVT_R4K +- select CLKSRC_MIPS_GIC + select COMMON_CLK + select CPU_MIPSR2_IRQ_EI + select CPU_MIPSR2_IRQ_VI +- select CSRC_R4K + select DMA_NONCOHERENT + select HAVE_PCI + select IRQ_MIPS_CPU + select MIPS_AUTO_PFN_OFFSET + select MIPS_CPU_SCACHE + select MIPS_GIC ++ select CLKSRC_MIPS_GIC if !QEMUMIPS64 ++ select CSRC_R4K if !QEMUMIPS64 + select MIPS_L1_CACHE_SHIFT_7 + select NO_EXCEPT_FILL + select PCI_DRIVERS_GENERIC +@@ -546,9 +550,9 @@ config MIPS_MALTA + select BOOT_RAW + select BUILTIN_DTB + select CEVT_R4K +- select CLKSRC_MIPS_GIC ++ select CLKSRC_MIPS_GIC if !QEMUMIPS64 ++ select CSRC_R4K if !QEMUMIPS64 + select COMMON_CLK +- select CSRC_R4K + select DMA_NONCOHERENT + select GENERIC_ISA_DMA + select HAVE_PCSPKR_PLATFORM +-- +2.19.1 + |