commit 7aab93aa0fdde3db4b9fd0ed9362b80479a7cba3
parent edbce4510998845c7ed2641373981a3167d0e7bd
Author: Ryan Sepassi <rsepassi@gmail.com>
Date: Tue, 5 May 2026 11:08:28 -0700
boot.sh e2e kernel + podman
Diffstat:
2 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/scripts/boot.sh b/scripts/boot.sh
@@ -1,8 +1,32 @@
#!/bin/sh
+## boot.sh — drive boot0 → boot5 end-to-end under one driver.
+##
+## Usage: scripts/boot.sh <arch>
+## DRIVER=seed scripts/boot.sh aarch64
+## DRIVER=podman scripts/boot.sh <amd64|aarch64|riscv64>
+##
+## DRIVER (default podman) is exported and consumed by each bootN.sh.
+## DRIVER=seed is aarch64-only and requires seed-kernel/build/Image.
set -ex
ARCH=$1
+DRIVER=${DRIVER:-podman}
+
+case "$DRIVER" in
+ podman) ;;
+ seed)
+ [ "$ARCH" = aarch64 ] || { echo "[boot] DRIVER=seed: aarch64 only" >&2; exit 2; }
+ if [ ! -f seed-kernel/build/Image ]; then
+ echo "[boot] building seed-kernel/build/Image"
+ podman run --rm --pull=never --platform linux/arm64 \
+ -v "$PWD/seed-kernel:/work" -w /work boot2-alpine-gcc:aarch64 \
+ sh -c 'apk add --no-progress --quiet make >/dev/null 2>&1; make -s'
+ fi
+ ;;
+ *) echo "[boot] unknown DRIVER=$DRIVER (expected podman|seed)" >&2; exit 2 ;;
+esac
+export DRIVER
rm -rf build/$ARCH
diff --git a/seed-kernel/start.S b/seed-kernel/start.S
@@ -195,10 +195,39 @@ eret_to_user:
msr elr_el1, x0
mov x9, #0x3c4 /* EL1t, DAIF=1111 */
msr spsr_el1, x9
- /* Clear all GP regs so user starts clean (except x0..argc handled
- * via the SysV stack layout, which the user reads directly). */
+ /* Clear all GP regs so user starts clean. argc/argv come in via the
+ * SysV stack layout, which the user reads directly off SP_EL0. Some
+ * boot0/1 seed-stage binaries (notably M0) read xN before any write,
+ * so leaking kernel register state past the eret would fault them. */
mov x0, xzr
mov x1, xzr
mov x2, xzr
mov x3, xzr
+ mov x4, xzr
+ mov x5, xzr
+ mov x6, xzr
+ mov x7, xzr
+ mov x8, xzr
+ mov x9, xzr
+ mov x10, xzr
+ mov x11, xzr
+ mov x12, xzr
+ mov x13, xzr
+ mov x14, xzr
+ mov x15, xzr
+ mov x16, xzr
+ mov x17, xzr
+ mov x18, xzr
+ mov x19, xzr
+ mov x20, xzr
+ mov x21, xzr
+ mov x22, xzr
+ mov x23, xzr
+ mov x24, xzr
+ mov x25, xzr
+ mov x26, xzr
+ mov x27, xzr
+ mov x28, xzr
+ mov x29, xzr
+ mov x30, xzr
eret
