linux-kernel - Re: [PATCH v4 25/30] context_tracking,x86: Defer kernel text patching IPIs

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Message-ID: <Z4bWnWYqu1LaD-JG@google.com>
Date: Tue, 14 Jan 2025 13:26:53 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Valentin Schneider <vschneid@...hat.com>
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Subject: Re: [PATCH v4 25/30] context_tracking,x86: Defer kernel text patching IPIs

On Tue, Jan 14, 2025, Valentin Schneider wrote:
>  static __always_inline void arch_context_tracking_work(enum ct_work work)
>  {
>  	switch (work) {
> -	case CT_WORK_n:
> -		// Do work...
> +	case CT_WORK_SYNC:
> +		sync_core();

Not your bug, but serialize() needs to be __always_inline.  Not sure what exactly
caused it to be uninlined, but this is the obvious new usage.

vmlinux.o: warning: objtool: __static_call_update_early+0x4e: call to serialize() leaves .noinstr.text section
vmlinux.o: warning: objtool: ct_work_flush+0x69: call to serialize() leaves .noinstr.text section