From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ACCD12E285C for ; Tue, 13 Jan 2026 18:36:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768329368; cv=none; b=cp+Qi5iy91plhmrD8jhiQlkfZ4imdIBsHUvrtdqccTPxgCPxDdsvKlYisQBl1LAQpwkUc4bEFOpwrrZBe2Edvb0vGSLDCLdNFPSv8jnv4WCbeuJ+nykqtH8AEMa8JDwSshoTnn0TSuizq5neR54rLViqudqB+F22F7DZmIbvOEg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768329368; c=relaxed/simple; bh=waPBtMaWbPGlkrm/DtnNWB1BKXoDjj23sRuuXFc4iTI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Hx8c85EEBFVf1yQDqTwAitvrnrHQBKJjVx2hjxjzKGU5kz+jP6s1NEZyYum1/VITLlS5o+KkHn1Yy3piyJlq4gdULEWd9xLsvMOwfYgNKac6m+of0j/WvVRiWVpta93dE3Yy93UeOOGrk9h1plluZOTWLo2e/TCwapqY9YwhsMA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=hFImr025; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=xqkqfQnW; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="hFImr025"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="xqkqfQnW" Date: Tue, 13 Jan 2026 19:36:04 +0100 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1768329365; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=pipRsFX69esF5KPLH4c9+I4B/dXZBlcjVkgFMV18ALI=; b=hFImr025oHU3L771wHk/hH+l4KUX+6lGspsuzw6PbnGGkZ+sQxro5UaFtiyINrXh796G4K 00d1uB5mDQoevz9twPv15hzNWWdXn+XGhd+73I+SNexn4IkTU2nNSvy1PXxXwFdYjV7Gk9 9t60Vv1kdj8AMcNFoFoTiAxaF5EtVm/czMWoktNQGYXLTDDEuDg013/R83Zb3x/tnImXLL nNyWEzk2QC/wXLH30bUnesKMvtrB5A+VpDJ48BLku+F+m3Qpe06OguRMBqDXM5CuEBiK8e GrFZ/Y30sTDtwgkpKZzcjPhkrmyXA+KxJVSXJobJG/bTu0hdd3ya8SXDXd5Vyg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1768329365; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=pipRsFX69esF5KPLH4c9+I4B/dXZBlcjVkgFMV18ALI=; b=xqkqfQnWaqaQfZqfL4aBVEtYUtp9diagEpNuEMaq04JbGoa7muCgQh8Bb8gxJUlcg5uYA/ Wa0zRRjjiz3hY5AQ== From: Sebastian Andrzej Siewior To: Vlastimil Babka Cc: Harry Yoo , Petr Tesarik , Christoph Lameter , David Rientjes , Roman Gushchin , Hao Li , Andrew Morton , Uladzislau Rezki , "Liam R. Howlett" , Suren Baghdasaryan , Alexei Starovoitov , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-rt-devel@lists.linux.dev, bpf@vger.kernel.org, kasan-dev@googlegroups.com Subject: Re: [PATCH RFC v2 06/20] slab: make percpu sheaves compatible with kmalloc_nolock()/kfree_nolock() Message-ID: <20260113183604.ykHFYvV2@linutronix.de> References: <20260112-sheaves-for-all-v2-0-98225cfb50cf@suse.cz> <20260112-sheaves-for-all-v2-6-98225cfb50cf@suse.cz> Precedence: bulk X-Mailing-List: linux-rt-devel@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260112-sheaves-for-all-v2-6-98225cfb50cf@suse.cz> On 2026-01-12 16:17:00 [+0100], Vlastimil Babka wrote: > --- a/mm/slub.c > +++ b/mm/slub.c > @@ -5727,6 +5742,12 @@ void *kmalloc_nolock_noprof(size_t size, gfp_t gfp_flags, int node) > */ > return NULL; > > + ret = alloc_from_pcs(s, alloc_gfp, node); > + if (ret) > + goto success; I'm sorry if I am slow but this actually should actually allow kmalloc_nolock() allocations on PREEMPT_RT from atomic context. I am mentioning this because of the patch which removes the nmi+hardirq condtion (https://lore.kernel.org/all/20260113150639.48407-1-swarajgaikwad1925@gmail.com) > + > + ret = ERR_PTR(-EBUSY); > + > /* > * Do not call slab_alloc_node(), since trylock mode isn't > * compatible with slab_pre_alloc_hook/should_failslab and Sebastian