linux-kernel - Re: [PATCH] slab: fix kmalloc_nolock() context check for PREEMPT

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Message-ID: <20251219135143.7337-1-swarajgaikwad1925@gmail.com>
Date: Fri, 19 Dec 2025 19:21:43 +0530
From: Swaraj Gaikwad <swarajgaikwad1925@...il.com>
To: lgoncalv@...hat.com
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Subject: Re: [PATCH] slab: fix kmalloc_nolock() context check for PREEMPT_RT

I agree that we can simplify this. I think !preemptible() would be
the most descriptive choice here, as it directly expresses the
constraint, we cannot take a sleeping lock when preemption is
disabled.
The updated check would be:
    if (IS_ENABLED(CONFIG_PREEMPT_RT) && !preemptible())

I'll send a v2 with this change unless there are objections.

Swaraj