[PATCH 5.18 001/879] arm64: Initialize jump labels before setup_machine_fdt()

Greg Kroah-Hartman
2022-06-07T21:54:51Z

From: Stephen Boyd <swboyd@chromium.org>

commit 73e2d827a501d48dceeb5b9b267a4cd283d6b1ae upstream.

A static key warning splat appears during early boot on arm64 systems
that credit randomness from devicetrees that contain an "rng-seed"
property. This is because setup_machine_fdt() is called before
jump_label_init() during setup_arch(). Let's swap the order of these two
calls so that jump labels are initialized before the devicetree is
unflattened and the rng seed is credited.

static_key_enable_cpuslocked(): static key '0xffffffe51c6fcfc0' used before call to jump_label_init()
WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xb0/0xb8
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 5.18.0+ #224 44b43e377bfc84bc99bb5ab885ff694984ee09ff
pstate: 600001c9 (nZCv dAIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : static_key_enable_cpuslocked+0xb0/0xb8
lr : static_key_enable_cpuslocked+0xb0/0xb8
sp : ffffffe51c393cf0
x29: ffffffe51c393cf0 x28: 000000008185054c x27: 00000000f1042f10
x26: 0000000000000000 x25: 00000000f10302b2 x24: 0000002513200000
x23: 0000002513200000 x22: ffffffe51c1c9000 x21: fffffffdfdc00000
x20: ffffffe51c2f0831 x19: ffffffe51c6fcfc0 x18: 00000000ffff1020
x17: 00000000e1e2ac90 x16: 00000000000000e0 x15: ffffffe51b710708
x14: 0000000000000066 x13: 0000000000000018 x12: 0000000000000000
x11: 0000000000000000 x10: 00000000ffffffff x9 : 0000000000000000
x8 : 0000000000000000 x7 : 61632065726f6665 x6 : 6220646573752027
x5 : ffffffe51c641d25 x4 : ffffffe51c13142c x3 : ffff0a00ffffff05
x2 : 40000000ffffe003 x1 : 00000000000001c0 x0 : 0000000000000065
Call trace:
static_key_enable_cpuslocked+0xb0/0xb8
static_key_enable+0x2c/0x40
crng_set_ready+0x24/0x30
execute_in_process_context+0x80/0x90
_credit_init_bits+0x100/0x154
add_bootloader_randomness+0x64/0x78
early_init_dt_scan_chosen+0x140/0x184
early_init_dt_scan_nodes+0x28/0x4c
early_init_dt_scan+0x40/0x44
setup_machine_fdt+0x7c/0x120
setup_arch+0x74/0x1d8
start_kernel+0x84/0x44c
__primary_switched+0xc0/0xc8
---[ end trace 0000000000000000 ]---
random: crng init done
Machine model: Google Lazor (rev1 - 2) with LTE

Cc: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Douglas Anderson <dianders@chromium.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Fixes: f5bda35fba61 ("random: use static branch for crng_ready()")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20220602022109.780348-1-swboyd@chromium.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/arm64/kernel/setup.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -314,13 +314,14 @@ void __init __no_sanitize_address setup_
early_fixmap_init();
early_ioremap_init();

- setup_machine_fdt(__fdt_pointer);
-
/*
* Initialise the static keys early as they may be enabled by the
- * cpufeature code and early parameters.
+ * cpufeature code, early parameters, and DT setup.
*/
jump_label_init();
+
+ setup_machine_fdt(__fdt_pointer);
+
parse_early_param();

/*