From b2b49fbd7724cf6bede9964e786ecf564d4ab17d Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jeremy@system76.com>
Date: Tue, 23 Feb 2021 09:23:37 -0700
Subject: [PATCH] Update kernel and makefiles to enable use of GS segment

---
 kernel          |  2 +-
 mk/kernel.mk    | 12 ++++++------
 mk/kernel_ld.sh | 17 +++++++++++++++++
 3 files changed, 24 insertions(+), 7 deletions(-)
 create mode 100755 mk/kernel_ld.sh

diff --git a/kernel b/kernel
index ba330ff..f873fc7 160000
--- a/kernel
+++ b/kernel
@@ -1 +1 @@
-Subproject commit ba330ffc9abdb07d59ca3c5b386f07e4fb26d870
+Subproject commit f873fc7e1a20ac9a5630ec031a086903d2917792
diff --git a/mk/kernel.mk b/mk/kernel.mk
index b6634bd..1adbfa6 100644
--- a/mk/kernel.mk
+++ b/mk/kernel.mk
@@ -16,21 +16,21 @@ build/libkernel_live.a: kernel/Cargo.toml kernel/src/* kernel/src/*/* kernel/src
 	cd kernel && \
 	cargo rustc --lib --target=$(ROOT)/kernel/targets/$(KTARGET).json --release --features live -Z build-std=core,alloc -- -C soft-float -C debuginfo=2 -C lto --emit link=../$@
 
-build/kernel: kernel/linkers/$(ARCH).ld build/libkernel.a
+build/kernel: kernel/linkers/$(ARCH).ld mk/kernel_ld.sh build/libkernel.a
 	export PATH="$(PREFIX_PATH):$$PATH" && \
-	$(LD) --gc-sections -z max-page-size=0x1000 -T $< -o $@ build/libkernel.a && \
+	$(ROOT)/mk/kernel_ld.sh $(LD) --gc-sections -z max-page-size=0x1000 -T $< -o $@ build/libkernel.a && \
 	$(OBJCOPY) --only-keep-debug $@ $@.sym && \
 	$(OBJCOPY) --strip-debug $@
 
-build/kernel_coreboot: kernel/linkers/$(ARCH).ld build/libkernel_coreboot.a build/live.o
+build/kernel_coreboot: kernel/linkers/$(ARCH).ld mk/kernel_ld.sh build/libkernel_coreboot.a build/live.o
 	export PATH="$(PREFIX_PATH):$$PATH" && \
-	$(LD) --gc-sections -z max-page-size=0x1000 -T $< -o $@ build/libkernel_coreboot.a build/live.o && \
+	$(ROOT)/mk/kernel_ld.sh $(LD) --gc-sections -z max-page-size=0x1000 -T $< -o $@ build/libkernel_coreboot.a build/live.o && \
 	$(OBJCOPY) --only-keep-debug $@ $@.sym && \
 	$(OBJCOPY) --strip-debug $@
 
-build/kernel_live: kernel/linkers/$(ARCH).ld build/libkernel_live.a build/live.o
+build/kernel_live: kernel/linkers/$(ARCH).ld mk/kernel_ld.sh build/libkernel_live.a build/live.o
 	export PATH="$(PREFIX_PATH):$$PATH" && \
-	$(LD) --gc-sections -z max-page-size=0x1000 -T $< -o $@ build/libkernel_live.a build/live.o && \
+	$(ROOT)/mk/kernel_ld.sh $(LD) --gc-sections -z max-page-size=0x1000 -T $< -o $@ build/libkernel_live.a build/live.o && \
 	$(OBJCOPY) --only-keep-debug $@ $@.sym && \
 	$(OBJCOPY) --strip-debug $@
 
diff --git a/mk/kernel_ld.sh b/mk/kernel_ld.sh
new file mode 100755
index 0000000..0f82b89
--- /dev/null
+++ b/mk/kernel_ld.sh
@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+set -ex
+
+LD="$1"
+shift
+
+if "${LD}" -z use-gs-for-tls 2>&1 |
+grep "warning: -z use-gs-for-tls ignored" &> /dev/null
+then
+	echo "Please update your prefix:" >&2
+	echo "  rm -rf prefix" >&2
+	echo "  make prefix" >&2
+	exit 1
+fi
+
+exec "${LD}" -z use-gs-for-tls "$@"