Re: [PATCH stable 5.10 5.15 5.17 5.18] arm64: Initialize jump labels before setup_machine_fdt()

[Greg KH <gregkh@linuxfoundation.org>]

On Sat, Jun 04, 2022 at 08:25:03AM +0200, Jason A. Donenfeld wrote:
> 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>
> ---
> This got a "Fixes:" tag, but didn't have a corresponding Cc to stable.
> Presumably AUTOSEL will eventually find this too, but sending it onward
> proactively anyway.

Now queued up, thanks.

greg k-h