Rebuilding against gcc >= 10.1.0

Adding upstream patches for gcc >= 10.1.0 compatibility.
Adding patch for sphinx problems, instead of using sed.

8 files changed, 647 insertions, 8 deletions

diff --git a/.SRCINFO b/.SRCINFO
index a0776ede7740..2abcf6ccefca 100644
--- a/.SRCINFO
+++ b/.SRCINFO
@@ -1,7 +1,7 @@
 pkgbase = linux-rt
 	pkgdesc = Linux RT
 	pkgver = 5.6.10.5
-	pkgrel = 1
+	pkgrel = 2
 	url = https://wiki.linuxfoundation.org/realtime/start
 	arch = x86_64
 	license = GPL2
@@ -21,6 +21,12 @@ pkgbase = linux-rt
 	source = https://www.kernel.org/pub/linux/kernel/projects/rt/5.6/older/patch-5.6.10-rt5.patch.sign
 	source = config
 	source = 0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
+	source = sphinx-workaround.patch
+	source = 0001-kvm-ioapic-Restrict-lazy-EOI-update-to-edge-triggere.patch
+	source = 0002-gcc-plugins-drop-support-for-GCC-4.7.patch
+	source = 0003-gcc-common.h-Update-for-GCC-10.patch
+	source = 0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch
+	source = 0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch
 	validpgpkeys = ABAF11C65A2970B130ABE3C479BE3E4300411886
 	validpgpkeys = 647F28654894E3BD457199BE38DBBDC86092693E
 	validpgpkeys = 8218F88849AAC522E94CF470A5E9288C4FA415FA
@@ -33,6 +39,12 @@ pkgbase = linux-rt
 	sha256sums = SKIP
 	sha256sums = d7203e4d164a7040de524227a072ae3d5155cffb905762af9e12ae224b131245
 	sha256sums = ad3275a696348703c57f05b9626e7fbab7243299da32e52044ff51666f810e85
+	sha256sums = 8cb21e0b3411327b627a9dd15b8eb773295a0d2782b1a41b2a8839d1b2f5778c
+	sha256sums = 2776ca0b3ca95347518b146aab54fb564d138dfc7310c48141bed6cea98a8a07
+	sha256sums = 96ff333774c0a8686c41610364f13e5244946c86e3e12e841e1bbd0d9f33c788
+	sha256sums = 523280e5d125a19af537ee88a531b56a049f3daeb713da473d244eb423f6125f
+	sha256sums = 7462399703b4017aae39178991775beedd20269100e907c5f0cea3f78e5d825b
+	sha256sums = 585a1320b0c7e42a4ed152bb671288ce992271a4a52a6fffcae5ecaf805ecbce
 
 pkgname = linux-rt
 	pkgdesc = The Linux RT kernel and modules
diff --git a/0001-kvm-ioapic-Restrict-lazy-EOI-update-to-edge-triggere.patch b/0001-kvm-ioapic-Restrict-lazy-EOI-update-to-edge-triggere.patch
new file mode 100644
index 000000000000..966b69b73859
--- /dev/null
+++ b/0001-kvm-ioapic-Restrict-lazy-EOI-update-to-edge-triggere.patch
@@ -0,0 +1,79 @@
+From da707adaee9ff035c943178160be54a90de00cb3 Mon Sep 17 00:00:00 2001
+From: Paolo Bonzini <pbonzini@redhat.com>
+Date: Mon, 4 May 2020 12:19:45 -0400
+Subject: [PATCH 1/5] kvm: ioapic: Restrict lazy EOI update to edge-triggered
+ interrupts
+
+Commit f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI") introduces
+the following infinite loop:
+
+BUG: stack guard page was hit at 000000008f595917 \
+(stack is 00000000bdefe5a4..00000000ae2b06f5)
+kernel stack overflow (double-fault): 0000 [#1] SMP NOPTI
+RIP: 0010:kvm_set_irq+0x51/0x160 [kvm]
+Call Trace:
+ irqfd_resampler_ack+0x32/0x90 [kvm]
+ kvm_notify_acked_irq+0x62/0xd0 [kvm]
+ kvm_ioapic_update_eoi_one.isra.0+0x30/0x120 [kvm]
+ ioapic_set_irq+0x20e/0x240 [kvm]
+ kvm_ioapic_set_irq+0x5c/0x80 [kvm]
+ kvm_set_irq+0xbb/0x160 [kvm]
+ ? kvm_hv_set_sint+0x20/0x20 [kvm]
+ irqfd_resampler_ack+0x32/0x90 [kvm]
+ kvm_notify_acked_irq+0x62/0xd0 [kvm]
+ kvm_ioapic_update_eoi_one.isra.0+0x30/0x120 [kvm]
+ ioapic_set_irq+0x20e/0x240 [kvm]
+ kvm_ioapic_set_irq+0x5c/0x80 [kvm]
+ kvm_set_irq+0xbb/0x160 [kvm]
+ ? kvm_hv_set_sint+0x20/0x20 [kvm]
+....
+
+The re-entrancy happens because the irq state is the OR of
+the interrupt state and the resamplefd state.  That is, we don't
+want to show the state as 0 until we've had a chance to set the
+resamplefd.  But if the interrupt has _not_ gone low then
+ioapic_set_irq is invoked again, causing an infinite loop.
+
+This can only happen for a level-triggered interrupt, otherwise
+irqfd_inject would immediately set the KVM_USERSPACE_IRQ_SOURCE_ID high
+and then low.  Fortunately, in the case of level-triggered interrupts the VMEXIT already happens because
+TMR is set.  Thus, fix the bug by restricting the lazy invocation
+of the ack notifier to edge-triggered interrupts, the only ones that
+need it.
+
+Tested-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
+Reported-by: borisvk@bstnet.org
+Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
+Link: https://www.spinics.net/lists/kvm/msg213512.html
+Fixes: f458d039db7e ("kvm: ioapic: Lazy update IOAPIC EOI")
+Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=207489
+Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
+---
+ arch/x86/kvm/ioapic.c | 10 +++++-----
+ 1 file changed, 5 insertions(+), 5 deletions(-)
+
+diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c
+index 750ff0b29404..d057376bd3d3 100644
+--- a/arch/x86/kvm/ioapic.c
++++ b/arch/x86/kvm/ioapic.c
+@@ -225,12 +225,12 @@ static int ioapic_set_irq(struct kvm_ioapic *ioapic, unsigned int irq,
+ 	}
+ 
+ 	/*
+-	 * AMD SVM AVIC accelerate EOI write and do not trap,
+-	 * in-kernel IOAPIC will not be able to receive the EOI.
+-	 * In this case, we do lazy update of the pending EOI when
+-	 * trying to set IOAPIC irq.
++	 * AMD SVM AVIC accelerate EOI write iff the interrupt is edge
++	 * triggered, in which case the in-kernel IOAPIC will not be able
++	 * to receive the EOI.  In this case, we do a lazy update of the
++	 * pending EOI when trying to set IOAPIC irq.
+ 	 */
+-	if (kvm_apicv_activated(ioapic->kvm))
++	if (edge && kvm_apicv_activated(ioapic->kvm))
+ 		ioapic_lazy_update_eoi(ioapic, irq);
+ 
+ 	/*
+-- 
+2.26.2
+
diff --git a/0002-gcc-plugins-drop-support-for-GCC-4.7.patch b/0002-gcc-plugins-drop-support-for-GCC-4.7.patch
new file mode 100644
index 000000000000..a392036109e3
--- /dev/null
+++ b/0002-gcc-plugins-drop-support-for-GCC-4.7.patch
@@ -0,0 +1,278 @@
+From dba68a9d4df76d49d32245e4236713a43fb321da Mon Sep 17 00:00:00 2001
+From: Masahiro Yamada <masahiroy@kernel.org>
+Date: Sun, 29 Mar 2020 20:08:32 +0900
+Subject: [PATCH 2/5] gcc-plugins: drop support for GCC <= 4.7
+
+Nobody was opposed to raising minimum GCC version to 4.8 [1]
+So, we will drop GCC <= 4.7 support sooner or later.
+
+We always use C++ compiler for building plugins for GCC >= 4.8.
+
+This commit drops the plugin support for GCC <= 4.7 a bit earlier,
+which allows us to dump lots of code.
+
+[1] https://lkml.org/lkml/2020/1/23/545
+
+Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
+Acked-by: Kees Cook <keescook@chromium.org>
+---
+ scripts/Kconfig.include      |  3 --
+ scripts/Makefile.build       |  2 +-
+ scripts/Makefile.clean       |  1 -
+ scripts/Makefile.host        | 23 +--------------
+ scripts/gcc-plugin.sh        | 57 ++++--------------------------------
+ scripts/gcc-plugins/Kconfig  | 12 ++------
+ scripts/gcc-plugins/Makefile | 21 ++++---------
+ 7 files changed, 15 insertions(+), 104 deletions(-)
+
+diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
+index 496d11c92c97..033f6efd92d3 100644
+--- a/scripts/Kconfig.include
++++ b/scripts/Kconfig.include
+@@ -42,9 +42,6 @@ $(error-if,$(failure,command -v $(LD)),linker '$(LD)' not found)
+ # Fail if the linker is gold as it's not capable of linking the kernel proper
+ $(error-if,$(success, $(LD) -v | grep -q gold), gold linker '$(LD)' not supported)
+ 
+-# gcc version including patch level
+-gcc-version := $(shell,$(srctree)/scripts/gcc-version.sh $(CC))
+-
+ # machine bit flags
+ #  $(m32-flag): -m32 if the compiler supports it, or an empty string otherwise.
+ #  $(m64-flag): -m64 if the compiler supports it, or an empty string otherwise.
+diff --git a/scripts/Makefile.build b/scripts/Makefile.build
+index a1730d42e5f3..eec789d7a63a 100644
+--- a/scripts/Makefile.build
++++ b/scripts/Makefile.build
+@@ -46,7 +46,7 @@ include $(kbuild-file)
+ include scripts/Makefile.lib
+ 
+ # Do not include host rules unless needed
+-ifneq ($(hostprogs)$(hostlibs-y)$(hostlibs-m)$(hostcxxlibs-y)$(hostcxxlibs-m),)
++ifneq ($(hostprogs)$(hostcxxlibs-y)$(hostcxxlibs-m),)
+ include scripts/Makefile.host
+ endif
+ 
+diff --git a/scripts/Makefile.clean b/scripts/Makefile.clean
+index 1e4206566a82..075f0cc2d8d7 100644
+--- a/scripts/Makefile.clean
++++ b/scripts/Makefile.clean
+@@ -30,7 +30,6 @@ subdir-ymn	:= $(addprefix $(obj)/,$(subdir-ymn))
+ __clean-files	:= $(extra-y) $(extra-m) $(extra-)       \
+ 		   $(always) $(always-y) $(always-m) $(always-) $(targets) $(clean-files)   \
+ 		   $(hostprogs) $(hostprogs-y) $(hostprogs-m) $(hostprogs-) \
+-		   $(hostlibs-y) $(hostlibs-m) $(hostlibs-) \
+ 		   $(hostcxxlibs-y) $(hostcxxlibs-m)
+ 
+ __clean-files   := $(filter-out $(no-clean-files), $(__clean-files))
+diff --git a/scripts/Makefile.host b/scripts/Makefile.host
+index 3b7121d43324..2045855d0b75 100644
+--- a/scripts/Makefile.host
++++ b/scripts/Makefile.host
+@@ -39,7 +39,6 @@ $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE
+ # They are linked as C++ code to the executable qconf
+ 
+ __hostprogs := $(sort $(hostprogs))
+-host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m))
+ host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m))
+ 
+ # C code
+@@ -63,7 +62,6 @@ host-cxxmulti	:= $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m)))
+ host-cxxobjs	:= $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs)))
+ 
+ # Object (.o) files used by the shared libaries
+-host-cshobjs	:= $(sort $(foreach m,$(host-cshlib),$($(m:.so=-objs))))
+ host-cxxshobjs	:= $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs))))
+ 
+ host-csingle	:= $(addprefix $(obj)/,$(host-csingle))
+@@ -71,9 +69,7 @@ host-cmulti	:= $(addprefix $(obj)/,$(host-cmulti))
+ host-cobjs	:= $(addprefix $(obj)/,$(host-cobjs))
+ host-cxxmulti	:= $(addprefix $(obj)/,$(host-cxxmulti))
+ host-cxxobjs	:= $(addprefix $(obj)/,$(host-cxxobjs))
+-host-cshlib	:= $(addprefix $(obj)/,$(host-cshlib))
+ host-cxxshlib	:= $(addprefix $(obj)/,$(host-cxxshlib))
+-host-cshobjs	:= $(addprefix $(obj)/,$(host-cshobjs))
+ host-cxxshobjs	:= $(addprefix $(obj)/,$(host-cxxshobjs))
+ 
+ #####
+@@ -140,13 +136,6 @@ quiet_cmd_host-cxxobjs	= HOSTCXX $@
+ $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE
+ 	$(call if_changed_dep,host-cxxobjs)
+ 
+-# Compile .c file, create position independent .o file
+-# host-cshobjs -> .o
+-quiet_cmd_host-cshobjs	= HOSTCC  -fPIC $@
+-      cmd_host-cshobjs	= $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $<
+-$(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE
+-	$(call if_changed_dep,host-cshobjs)
+-
+ # Compile .c file, create position independent .o file
+ # Note that plugin capable gcc versions can be either C or C++ based
+ # therefore plugin source files have to be compilable in both C and C++ mode.
+@@ -157,16 +146,6 @@ quiet_cmd_host-cxxshobjs	= HOSTCXX -fPIC $@
+ $(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE
+ 	$(call if_changed_dep,host-cxxshobjs)
+ 
+-# Link a shared library, based on position independent .o files
+-# *.o -> .so shared library (host-cshlib)
+-quiet_cmd_host-cshlib	= HOSTLLD -shared $@
+-      cmd_host-cshlib	= $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \
+-			  $(addprefix $(obj)/, $($(target-stem)-objs)) \
+-			  $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem).so)
+-$(host-cshlib): FORCE
+-	$(call if_changed,host-cshlib)
+-$(call multi_depend, $(host-cshlib), .so, -objs)
+-
+ # Link a shared library, based on position independent .o files
+ # *.o -> .so shared library (host-cxxshlib)
+ quiet_cmd_host-cxxshlib	= HOSTLLD -shared $@
+@@ -178,4 +157,4 @@ $(host-cxxshlib): FORCE
+ $(call multi_depend, $(host-cxxshlib), .so, -objs)
+ 
+ targets += $(host-csingle)  $(host-cmulti) $(host-cobjs)\
+-	   $(host-cxxmulti) $(host-cxxobjs) $(host-cshlib) $(host-cshobjs) $(host-cxxshlib) $(host-cxxshobjs)
++	   $(host-cxxmulti) $(host-cxxobjs) $(host-cxxshlib) $(host-cxxshobjs)
+diff --git a/scripts/gcc-plugin.sh b/scripts/gcc-plugin.sh
+index d3caefe53eab..b79fd0bea838 100755
+--- a/scripts/gcc-plugin.sh
++++ b/scripts/gcc-plugin.sh
+@@ -1,49 +1,14 @@
+ #!/bin/sh
+ # SPDX-License-Identifier: GPL-2.0
++
++set -e
++
+ srctree=$(dirname "$0")
+ 
+-SHOW_ERROR=
+-if [ "$1" = "--show-error" ] ; then
+-	SHOW_ERROR=1
+-	shift || true
+-fi
+-
+-gccplugins_dir=$($3 -print-file-name=plugin)
+-plugincc=$($1 -E -x c++ - -o /dev/null -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF
+-#include "gcc-common.h"
+-#if BUILDING_GCC_VERSION >= 4008 || defined(ENABLE_BUILD_WITH_CXX)
+-#warning $2 CXX
+-#else
+-#warning $1 CC
+-#endif
+-EOF
+-)
+-
+-if [ $? -ne 0 ]
+-then
+-	if [ -n "$SHOW_ERROR" ] ; then
+-		echo "${plugincc}" >&2
+-	fi
+-	exit 1
+-fi
+-
+-case "$plugincc" in
+-	*"$1 CC"*)
+-		echo "$1"
+-		exit 0
+-		;;
+-
+-	*"$2 CXX"*)
+-		# the c++ compiler needs another test, see below
+-		;;
+-
+-	*)
+-		exit 1
+-		;;
+-esac
++gccplugins_dir=$($* -print-file-name=plugin)
+ 
+ # we need a c++ compiler that supports the designated initializer GNU extension
+-plugincc=$($2 -c -x c++ -std=gnu++98 - -fsyntax-only -I"${srctree}"/gcc-plugins -I"${gccplugins_dir}"/include 2>&1 <<EOF
++$HOSTCC -c -x c++ -std=gnu++98 - -fsyntax-only -I $srctree/gcc-plugins -I $gccplugins_dir/include 2>/dev/null <<EOF
+ #include "gcc-common.h"
+ class test {
+ public:
+@@ -52,15 +17,3 @@ public:
+ 	.test = 1
+ };
+ EOF
+-)
+-
+-if [ $? -eq 0 ]
+-then
+-	echo "$2"
+-	exit 0
+-fi
+-
+-if [ -n "$SHOW_ERROR" ] ; then
+-	echo "${plugincc}" >&2
+-fi
+-exit 1
+diff --git a/scripts/gcc-plugins/Kconfig b/scripts/gcc-plugins/Kconfig
+index e3569543bdac..fd31ed5b435f 100644
+--- a/scripts/gcc-plugins/Kconfig
++++ b/scripts/gcc-plugins/Kconfig
+@@ -1,13 +1,4 @@
+ # SPDX-License-Identifier: GPL-2.0-only
+-preferred-plugin-hostcc := $(if-success,[ $(gcc-version) -ge 40800 ],$(HOSTCXX),$(HOSTCC))
+-
+-config PLUGIN_HOSTCC
+-	string
+-	default "$(shell,$(srctree)/scripts/gcc-plugin.sh "$(preferred-plugin-hostcc)" "$(HOSTCXX)" "$(CC)")" if CC_IS_GCC
+-	help
+-	  Host compiler used to build GCC plugins.  This can be $(HOSTCXX),
+-	  $(HOSTCC), or a null string if GCC plugin is unsupported.
+-
+ config HAVE_GCC_PLUGINS
+ 	bool
+ 	help
+@@ -17,7 +8,8 @@ config HAVE_GCC_PLUGINS
+ menuconfig GCC_PLUGINS
+ 	bool "GCC plugins"
+ 	depends on HAVE_GCC_PLUGINS
+-	depends on PLUGIN_HOSTCC != ""
++	depends on CC_IS_GCC && GCC_VERSION >= 40800
++	depends on $(success,$(srctree)/scripts/gcc-plugin.sh $(CC))
+ 	default y
+ 	help
+ 	  GCC plugins are loadable modules that provide extra features to the
+diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile
+index f2ee8bd7abc6..f22858b2c3d6 100644
+--- a/scripts/gcc-plugins/Makefile
++++ b/scripts/gcc-plugins/Makefile
+@@ -1,18 +1,9 @@
+ # SPDX-License-Identifier: GPL-2.0
+-PLUGINCC := $(CONFIG_PLUGIN_HOSTCC:"%"=%)
+ GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin)
+ 
+-ifeq ($(PLUGINCC),$(HOSTCC))
+-  HOSTLIBS := hostlibs
+-  HOST_EXTRACFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu99 -ggdb
+-  export HOST_EXTRACFLAGS
+-else
+-  HOSTLIBS := hostcxxlibs
+-  HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti
+-  HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
+-  HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable
+-  export HOST_EXTRACXXFLAGS
+-endif
++HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti
++HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
++HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat
+ 
+ $(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h
+ quiet_cmd_create_randomize_layout_seed = GENSEED $@
+@@ -22,9 +13,9 @@ $(objtree)/$(obj)/randomize_layout_seed.h: FORCE
+ 	$(call if_changed,create_randomize_layout_seed)
+ targets = randomize_layout_seed.h randomize_layout_hash.h
+ 
+-$(HOSTLIBS)-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p)))
+-always-y := $($(HOSTLIBS)-y)
++hostcxxlibs-y := $(foreach p,$(GCC_PLUGIN),$(if $(findstring /,$(p)),,$(p)))
++always-y := $(hostcxxlibs-y)
+ 
+-$(foreach p,$($(HOSTLIBS)-y:%.so=%),$(eval $(p)-objs := $(p).o))
++$(foreach p,$(hostcxxlibs-y:%.so=%),$(eval $(p)-objs := $(p).o))
+ 
+ clean-files += *.so
+-- 
+2.26.2
+
diff --git a/0003-gcc-common.h-Update-for-GCC-10.patch b/0003-gcc-common.h-Update-for-GCC-10.patch
new file mode 100644
index 000000000000..8a8573ae72b4
--- /dev/null
+++ b/0003-gcc-common.h-Update-for-GCC-10.patch
@@ -0,0 +1,86 @@
+From 41e53fdbbf5121960fd44427c2ae7536d8fdd701 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Fr=C3=A9d=C3=A9ric=20Pierret=20=28fepitre=29?=
+ <frederic.pierret@qubes-os.org>
+Date: Tue, 7 Apr 2020 13:32:59 +0200
+Subject: [PATCH 3/5] gcc-common.h: Update for GCC 10
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Remove "params.h" include, which has been dropped in GCC 10.
+
+Remove is_a_helper() macro, which is now defined in gimple.h, as seen
+when running './scripts/gcc-plugin.sh g++ g++ gcc':
+
+In file included from <stdin>:1:
+./gcc-plugins/gcc-common.h:852:13: error: redefinition of ‘static bool is_a_helper<T>::test(U*) [with U = const gimple; T = const ggoto*]’
+  852 | inline bool is_a_helper<const ggoto *>::test(const_gimple gs)
+      |             ^~~~~~~~~~~~~~~~~~~~~~~~~~
+In file included from ./gcc-plugins/gcc-common.h:125,
+                 from <stdin>:1:
+/usr/lib/gcc/x86_64-redhat-linux/10/plugin/include/gimple.h:1037:1: note: ‘static bool is_a_helper<T>::test(U*) [with U = const gimple; T = const ggoto*]’ previously declared here
+ 1037 | is_a_helper <const ggoto *>::test (const gimple *gs)
+      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Add -Wno-format-diag to scripts/gcc-plugins/Makefile to avoid
+meaningless warnings from error() formats used by plugins:
+
+scripts/gcc-plugins/structleak_plugin.c: In function ‘int plugin_init(plugin_name_args*, plugin_gcc_version*)’:
+scripts/gcc-plugins/structleak_plugin.c:253:12: warning: unquoted sequence of 2 consecutive punctuation characters ‘'-’ in format [-Wformat-diag]
+  253 |   error(G_("unknown option '-fplugin-arg-%s-%s'"), plugin_name, argv[i].key);
+      |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Signed-off-by: Frédéric Pierret (fepitre) <frederic.pierret@qubes-os.org>
+Link: https://lore.kernel.org/r/20200407113259.270172-1-frederic.pierret@qubes-os.org
+[kees: include -Wno-format-diag for plugin builds]
+Signed-off-by: Kees Cook <keescook@chromium.org>
+---
+ scripts/gcc-plugins/Makefile     | 1 +
+ scripts/gcc-plugins/gcc-common.h | 4 ++++
+ 2 files changed, 5 insertions(+)
+
+diff --git a/scripts/gcc-plugins/Makefile b/scripts/gcc-plugins/Makefile
+index f22858b2c3d6..80f354289eeb 100644
+--- a/scripts/gcc-plugins/Makefile
++++ b/scripts/gcc-plugins/Makefile
+@@ -4,6 +4,7 @@ GCC_PLUGINS_DIR := $(shell $(CC) -print-file-name=plugin)
+ HOST_EXTRACXXFLAGS += -I$(GCC_PLUGINS_DIR)/include -I$(src) -std=gnu++98 -fno-rtti
+ HOST_EXTRACXXFLAGS += -fno-exceptions -fasynchronous-unwind-tables -ggdb
+ HOST_EXTRACXXFLAGS += -Wno-narrowing -Wno-unused-variable -Wno-c++11-compat
++HOST_EXTRACXXFLAGS += -Wno-format-diag
+ 
+ $(obj)/randomize_layout_plugin.o: $(objtree)/$(obj)/randomize_layout_seed.h
+ quiet_cmd_create_randomize_layout_seed = GENSEED $@
+diff --git a/scripts/gcc-plugins/gcc-common.h b/scripts/gcc-plugins/gcc-common.h
+index 17f06079a712..9ad76b7f3f10 100644
+--- a/scripts/gcc-plugins/gcc-common.h
++++ b/scripts/gcc-plugins/gcc-common.h
+@@ -35,7 +35,9 @@
+ #include "ggc.h"
+ #include "timevar.h"
+ 
++#if BUILDING_GCC_VERSION < 10000
+ #include "params.h"
++#endif
+ 
+ #if BUILDING_GCC_VERSION <= 4009
+ #include "pointer-set.h"
+@@ -847,6 +849,7 @@ static inline gimple gimple_build_assign_with_ops(enum tree_code subcode, tree l
+ 	return gimple_build_assign(lhs, subcode, op1, op2 PASS_MEM_STAT);
+ }
+ 
++#if BUILDING_GCC_VERSION < 10000
+ template <>
+ template <>
+ inline bool is_a_helper<const ggoto *>::test(const_gimple gs)
+@@ -860,6 +863,7 @@ inline bool is_a_helper<const greturn *>::test(const_gimple gs)
+ {
+ 	return gs->code == GIMPLE_RETURN;
+ }
++#endif
+ 
+ static inline gasm *as_a_gasm(gimple stmt)
+ {
+-- 
+2.26.2
+
diff --git a/0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch b/0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch
new file mode 100644
index 000000000000..dc41a7f34561
--- /dev/null
+++ b/0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch
@@ -0,0 +1,32 @@
+From af805f5f1d2e61dd2cf907d9635f0abc66fe1197 Mon Sep 17 00:00:00 2001
+From: Sergei Trofimovich <slyfox@gentoo.org>
+Date: Tue, 17 Mar 2020 00:07:18 +0000
+Subject: [PATCH 4/5] Makefile: disallow data races on gcc-10 as well
+
+gcc-10 will rename --param=allow-store-data-races=0
+to -fno-allow-store-data-races.
+
+The flag change happened at https://gcc.gnu.org/PR92046.
+
+Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
+Acked-by: Jiri Kosina <jkosina@suse.cz>
+Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
+---
+ Makefile | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/Makefile b/Makefile
+index 5dedd6f9ad75..6899bfc9dc7b 100644
+--- a/Makefile
++++ b/Makefile
+@@ -714,6 +714,7 @@ endif
+ 
+ # Tell gcc to never replace conditional load with a non-conditional one
+ KBUILD_CFLAGS	+= $(call cc-option,--param=allow-store-data-races=0)
++KBUILD_CFLAGS	+= $(call cc-option,-fno-allow-store-data-races)
+ 
+ include scripts/Makefile.kcov
+ include scripts/Makefile.gcc-plugins
+-- 
+2.26.2
+
diff --git a/0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch b/0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch
new file mode 100644
index 000000000000..3ff1480b7d9b
--- /dev/null
+++ b/0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch
@@ -0,0 +1,131 @@
+From 309b6eca2e2605accf7a3b02b47b5c2732dbe543 Mon Sep 17 00:00:00 2001
+From: Borislav Petkov <bp@suse.de>
+Date: Wed, 22 Apr 2020 18:11:30 +0200
+Subject: [PATCH 5/5] x86: Fix early boot crash on gcc-10, next try
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+... or the odyssey of trying to disable the stack protector for the
+function which generates the stack canary value.
+
+The whole story started with Sergei reporting a boot crash with a kernel
+built with gcc-10:
+
+  Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary
+  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139
+  Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013
+  Call Trace:
+    dump_stack
+    panic
+    ? start_secondary
+    __stack_chk_fail
+    start_secondary
+    secondary_startup_64
+  -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary
+
+This happens because gcc-10 tail-call optimizes the last function call
+in start_secondary() - cpu_startup_entry() - and thus emits a stack
+canary check which fails because the canary value changes after the
+boot_init_stack_canary() call.
+
+To fix that, the initial attempt was to mark the one function which
+generates the stack canary with:
+
+  __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused)
+
+however, using the optimize attribute doesn't work cumulatively
+as the attribute does not add to but rather replaces previously
+supplied optimization options - roughly all -fxxx options.
+
+The key one among them being -fno-omit-frame-pointer and thus leading to
+not present frame pointer - frame pointer which the kernel needs.
+
+The next attempt to prevent compilers from tail-call optimizing
+the last function call cpu_startup_entry(), shy of carving out
+start_secondary() into a separate compilation unit and building it with
+-fno-stack-protector, is this one.
+
+The current solution is short and sweet, and reportedly, is supported by
+both compilers so let's see how far we'll get this time.
+
+Reported-by: Sergei Trofimovich <slyfox@gentoo.org>
+Signed-off-by: Borislav Petkov <bp@suse.de>
+Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
+Reviewed-by: Kees Cook <keescook@chromium.org>
+Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
+---
+ arch/x86/include/asm/stackprotector.h | 7 ++++++-
+ arch/x86/kernel/smpboot.c             | 8 ++++++++
+ arch/x86/xen/smp_pv.c                 | 1 +
+ include/linux/compiler.h              | 6 ++++++
+ 4 files changed, 21 insertions(+), 1 deletion(-)
+
+diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h
+index 91e29b6a86a5..9804a7957f4e 100644
+--- a/arch/x86/include/asm/stackprotector.h
++++ b/arch/x86/include/asm/stackprotector.h
+@@ -55,8 +55,13 @@
+ /*
+  * Initialize the stackprotector canary value.
+  *
+- * NOTE: this must only be called from functions that never return,
++ * NOTE: this must only be called from functions that never return
+  * and it must always be inlined.
++ *
++ * In addition, it should be called from a compilation unit for which
++ * stack protector is disabled. Alternatively, the caller should not end
++ * with a function call which gets tail-call optimized as that would
++ * lead to checking a modified canary value.
+  */
+ static __always_inline void boot_init_stack_canary(void)
+ {
+diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
+index 69881b2d446c..9674321ce3a3 100644
+--- a/arch/x86/kernel/smpboot.c
++++ b/arch/x86/kernel/smpboot.c
+@@ -262,6 +262,14 @@ static void notrace start_secondary(void *unused)
+ 
+ 	wmb();
+ 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
++
++	/*
++	 * Prevent tail call to cpu_startup_entry() because the stack protector
++	 * guard has been changed a couple of function calls up, in
++	 * boot_init_stack_canary() and must not be checked before tail calling
++	 * another function.
++	 */
++	prevent_tail_call_optimization();
+ }
+ 
+ /**
+diff --git a/arch/x86/xen/smp_pv.c b/arch/x86/xen/smp_pv.c
+index 802ee5bba66c..0cebe5db691d 100644
+--- a/arch/x86/xen/smp_pv.c
++++ b/arch/x86/xen/smp_pv.c
+@@ -92,6 +92,7 @@ asmlinkage __visible void cpu_bringup_and_idle(void)
+ 	cpu_bringup();
+ 	boot_init_stack_canary();
+ 	cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
++	prevent_tail_call_optimization();
+ }
+ 
+ void xen_smp_intr_free_pv(unsigned int cpu)
+diff --git a/include/linux/compiler.h b/include/linux/compiler.h
+index 034b0a644efc..732754d96039 100644
+--- a/include/linux/compiler.h
++++ b/include/linux/compiler.h
+@@ -356,4 +356,10 @@ static inline void *offset_to_ptr(const int *off)
+ /* &a[0] degrades to a pointer: a different type from an array */
+ #define __must_be_array(a)	BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
+ 
++/*
++ * This is needed in functions which generate the stack canary, see
++ * arch/x86/kernel/smpboot.c::start_secondary() for an example.
++ */
++#define prevent_tail_call_optimization()	asm("")
++
+ #endif /* __LINUX_COMPILER_H */
+-- 
+2.26.2
+
diff --git a/PKGBUILD b/PKGBUILD
index 6c638f5de33a..ccbb51944783 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -5,7 +5,7 @@ pkgbase=linux-rt
 _pkgver=5.6.10
 _rtpatchver=5
 pkgver="${_pkgver}.${_rtpatchver}"
-pkgrel=1
+pkgrel=2
 pkgdesc='Linux RT'
 arch=('x86_64')
 url="https://wiki.linuxfoundation.org/realtime/start"
@@ -20,7 +20,13 @@ source=(
   "https://www.kernel.org/pub/linux/kernel/projects/rt/${_pkgver%.*}/older/patch-${_pkgver}-rt${_rtpatchver}.patch.xz"
   "https://www.kernel.org/pub/linux/kernel/projects/rt/${_pkgver%.*}/older/patch-${_pkgver}-rt${_rtpatchver}.patch.sign"
   config
-  0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch)
+  0001-ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
+  sphinx-workaround.patch
+  0001-kvm-ioapic-Restrict-lazy-EOI-update-to-edge-triggere.patch
+  0002-gcc-plugins-drop-support-for-GCC-4.7.patch
+  0003-gcc-common.h-Update-for-GCC-10.patch
+  0004-Makefile-disallow-data-races-on-gcc-10-as-well.patch
+  0005-x86-Fix-early-boot-crash-on-gcc-10-next-try.patch)
 validpgpkeys=(
   'ABAF11C65A2970B130ABE3C479BE3E4300411886'  # Linus Torvalds
   '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
@@ -34,7 +40,13 @@ sha256sums=('7bdc96827a9db8de79cd13d74a1c5fe8915674f793e592387f2903cb225801b9'
             'f712f8225069bc2cc6cf5080724483dff871fb5bdf41bdeeeb00a0087a28c116'
             'SKIP'
             'd7203e4d164a7040de524227a072ae3d5155cffb905762af9e12ae224b131245'
-            'ad3275a696348703c57f05b9626e7fbab7243299da32e52044ff51666f810e85')
+            'ad3275a696348703c57f05b9626e7fbab7243299da32e52044ff51666f810e85'
+            '8cb21e0b3411327b627a9dd15b8eb773295a0d2782b1a41b2a8839d1b2f5778c'
+            '2776ca0b3ca95347518b146aab54fb564d138dfc7310c48141bed6cea98a8a07'
+            '96ff333774c0a8686c41610364f13e5244946c86e3e12e841e1bbd0d9f33c788'
+            '523280e5d125a19af537ee88a531b56a049f3daeb713da473d244eb423f6125f'
+            '7462399703b4017aae39178991775beedd20269100e907c5f0cea3f78e5d825b'
+            '585a1320b0c7e42a4ed152bb671288ce992271a4a52a6fffcae5ecaf805ecbce')
 
 export KBUILD_BUILD_HOST=archlinux
 export KBUILD_BUILD_USER=$pkgbase
@@ -59,10 +71,6 @@ prepare() {
     patch -Np1 < "../$src"
   done
 
-  # removing cdomain configuration (incompatible with python-sphinx >= 3.0.0):
-  # https://github.com/sphinx-doc/sphinx/issues/7421
-  sed -e "s/'cdomain',//" -i Documentation/conf.py
-
   echo "Setting config..."
   cp ../config .config
   make olddefconfig
diff --git a/sphinx-workaround.patch b/sphinx-workaround.patch
new file mode 100644
index 000000000000..1aa3f1c8f66e
--- /dev/null
+++ b/sphinx-workaround.patch
@@ -0,0 +1,13 @@
+diff --git i/Documentation/conf.py w/Documentation/conf.py
+index 3c7bdf4cd31f..9a0ced58a3e9 100644
+--- i/Documentation/conf.py
++++ w/Documentation/conf.py
+@@ -36,7 +36,7 @@ needs_sphinx = '1.3'
+ # Add any Sphinx extension module names here, as strings. They can be
+ # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
+ # ones.
+-extensions = ['kerneldoc', 'rstFlatTable', 'kernel_include', 'cdomain',
++extensions = ['kerneldoc', 'rstFlatTable', 'kernel_include',
+               'kfigure', 'sphinx.ext.ifconfig', 'automarkup',
+               'maintainers_include']
+