From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 C32C2354AE2; Fri, 13 Feb 2026 11:02:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770980573; cv=none; b=J6DyT5YwAHSzuO5F0wAJDQUDnL5i1J0EcYrhWFOe1AGrsEXoD9mGCxNQTuOUZlt49W94ku2F2bmIShIcjYGZH3lB8zZy0S3o+sdQD+Ou9Ry7LPrR/WsnsS/umtXT0VrFt3K18hiSU3emT31AbYMVOwuN4rVNvYwxTo5YtWIDyJY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770980573; c=relaxed/simple; bh=UaoXLDuKM7W4LVs2b+N6DWDNPZ7brGJ4dmoEN3+mt3k=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kBVSxtlh7EPIWFMEP2l0XdgLvzgJ5cj3MqyBREs5OB67LNa2l37zOdQnlANXyd4QphS9kSXDgQcZWoK84Jh1vbfIQo3qb0cCFlB7o2I2bQ3lsKXyMVJ2dkHPQjBPGKrrh8daUu60i1KeETKaIa572jp5NtOaut24YSsh7pGIrYU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=anFUloTR; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="anFUloTR" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=gGY9mjNmnYiEGqmmSKnj+anrGWP6cFH8GMKxfF8SvcI=; b=anFUloTR5e87QUrovEFgzRlF3N Bq0w6Vgz4WwzBvkH/RITWQQJGLciH8j9utNJjniRskXcA2/WRSaUphtk80EuMiQnft0qc/TqP7wrU NVgzxh34jK1COkrSmEcZmG4hNYDNie5hjbV5ppNHzCqajhg8yEMexyPS63MjfJ48wnR2txEYGyaWb R6UVmqfpGFTaQ857oPuRVhHc/ssfpkafSr/xecuIlZTYzVU0oEizM3epsnwIYSP4GdaP9rsLXZLOX cZqaBCdef/VRyTHXhRBjH4xtBCaMjreMqgv1pIKwKfyn6edQbH0oCjtYuOI9CIW0UH9+y/QN9pERM APfe3wEA==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vqqwX-0000000C7oQ-2xs7; Fri, 13 Feb 2026 11:02:38 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 1DC173007B5; Fri, 13 Feb 2026 12:02:37 +0100 (CET) Date: Fri, 13 Feb 2026 12:02:37 +0100 From: Peter Zijlstra To: John Hubbard Cc: Lorenzo Stoakes , Shuah Khan , Christian Brauner , Shuah Khan , "Liam R . Howlett" , Suren Baghdasaryan , Vlastimil Babka , pedro.falcato@gmail.com, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org, Oliver Sang , seanjc@google.com Subject: Re: [PATCH v3 3/3] selftests: pidfd: add tests for PIDFD_SELF_* Message-ID: <20260213110237.GC3031506@noisy.programming.kicks-ass.net> References: <5b0b8e1e-6f50-4e18-bf46-39b00376c26e@nvidia.com> <20250501114235.GP4198@noisy.programming.kicks-ass.net> <20250501124646.GC4356@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250501124646.GC4356@noisy.programming.kicks-ass.net> On Thu, May 01, 2025 at 02:46:46PM +0200, Peter Zijlstra wrote: > On Thu, May 01, 2025 at 01:42:35PM +0200, Peter Zijlstra wrote: > > On Wed, Oct 16, 2024 at 07:14:34PM -0700, John Hubbard wrote: > > > On 10/16/24 3:06 PM, Lorenzo Stoakes wrote: > > > > On Wed, Oct 16, 2024 at 02:00:27PM -0600, Shuah Khan wrote: > > > > > On 10/16/24 04:20, Lorenzo Stoakes wrote: > > > ... > > > > > > diff --git a/tools/testing/selftests/pidfd/pidfd.h b/tools/testing/selftests/pidfd/pidfd.h > > > > > > index 88d6830ee004..1640b711889b 100644 > > > > > > --- a/tools/testing/selftests/pidfd/pidfd.h > > > > > > +++ b/tools/testing/selftests/pidfd/pidfd.h > > > > > > @@ -50,6 +50,14 @@ > > > > > > #define PIDFD_NONBLOCK O_NONBLOCK > > > > > > #endif > > > > > > +/* System header file may not have this available. */ > > > > > > +#ifndef PIDFD_SELF_THREAD > > > > > > +#define PIDFD_SELF_THREAD -100 > > > > > > +#endif > > > > > > +#ifndef PIDFD_SELF_THREAD_GROUP > > > > > > +#define PIDFD_SELF_THREAD_GROUP -200 > > > > > > +#endif > > > > > > + > > > > > > > > > > As mentioned in my response to v1 patch: > > > > > > > > > > kselftest has dependency on "make headers" and tests include > > > > > headers from linux/ directory > > > > > > > > Right but that assumes you install the kernel headers on the build system, > > > > which is quite a painful thing to have to do when you are quickly iterating > > > > on a qemu setup. > > > > > > > > This is a use case I use all the time so not at all theoretical. > > > > > > > > > > This is turning out to be a fairly typical reaction from kernel > > > developers, when presented with the "you must first run make headers" > > > requirement for kselftests. > > > > > > Peter Zijlstra's "NAK NAK NAK" response [1] last year was the most > > > colorful, so I'll helpfully cite it here. :) > > > > Let me re-try this. > > > > This is driving me insane. I've spend the past _TWO_ days trying to > > build KVM selftests and I'm still failing. > > > > This is absolute atrocious crap and is costing me valuable time. > > > > Please fix this fucking selftests shit to just build. This is unusable > > garbage. > > So after spending more time trying to remember how to debug Makefiles (I > hate my life), I found that not only do I need this headers shit, the > kvm selftests Makefile is actively broken if you use: make O=foo > > -INSTALL_HDR_PATH = $(top_srcdir)/usr > +INSTALL_HDR_PATH = $(top_srcdir)/$(O)/usr > > > And then finally, I can do: > > make O=foo headers_install > make O=foo -C tools/testing/selftests/kvm/ > > So yeah, thank you very much for wasting my time *AGAIN*. And *AGAIN*.. this is still the state of things. Selftests are still hopelessly broken and useless. Maybe we should just delete the lot?