linux-ext4 - Re: [PATCH 1/1] mm: change inlined allocation helpers to account at the call site

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Thu, 4 Apr 2024 23:33:22 +0100
From: Matthew Wilcox <willy@...radead.org>
To: Suren Baghdasaryan <surenb@...gle.com>
Cc: akpm@...ux-foundation.org, joro@...tes.org, will@...nel.org,
	trond.myklebust@...merspace.com, anna@...nel.org, arnd@...db.de,
	herbert@...dor.apana.org.au, davem@...emloft.net, jikos@...nel.org,
	benjamin.tissoires@...hat.com, tytso@....edu, jack@...e.com,
	dennis@...nel.org, tj@...nel.org, cl@...ux.com,
	jakub@...udflare.com, penberg@...nel.org, rientjes@...gle.com,
	iamjoonsoo.kim@....com, vbabka@...e.cz, edumazet@...gle.com,
	kuba@...nel.org, pabeni@...hat.com, iommu@...ts.linux.dev,
	linux-kernel@...r.kernel.org, linux-nfs@...r.kernel.org,
	linux-acpi@...r.kernel.org, acpica-devel@...ts.linux.dev,
	linux-arch@...r.kernel.org, linux-crypto@...r.kernel.org,
	bpf@...r.kernel.org, linux-input@...r.kernel.org,
	linux-ext4@...r.kernel.org, linux-mm@...ck.org,
	netdev@...r.kernel.org, linux-security-module@...r.kernel.org,
	kent.overstreet@...ux.dev
Subject: Re: [PATCH 1/1] mm: change inlined allocation helpers to account at
 the call site

On Thu, Apr 04, 2024 at 03:17:43PM -0700, Suren Baghdasaryan wrote:
> Ironically, checkpatch generates warnings for these type casts:
> 
> WARNING: unnecessary cast may hide bugs, see
> http://c-faq.com/malloc/mallocnocast.html
> #425: FILE: include/linux/dma-fence-chain.h:90:
> + ((struct dma_fence_chain *)kmalloc(sizeof(struct dma_fence_chain),
> GFP_KERNEL))
> 
> I guess I can safely ignore them in this case (since we cast to the
> expected type)?

I find ignoring checkpatch to be a solid move 99% of the time.

I really don't like the codetags.  This is so much churn, and it could
all be avoided by just passing in _RET_IP_ or _THIS_IP_ depending on
whether we wanted to profile this function or its caller.  vmalloc
has done it this way since 2008 (OK, using __builtin_return_address())
and lockdep has used _THIS_IP_ / _RET_IP_ since 2006.