linux-kernel - Re: [PATCH] resource,kexec: walk_system_ram_res

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]

Message-ID: <ZxJ13aKBqEotI593@smile.fi.intel.com>
Date: Fri, 18 Oct 2024 17:51:09 +0300
From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To: Baoquan He <bhe@...hat.com>
Cc: Gregory Price <gourry@...rry.net>, kexec@...ts.infradead.org,
	linux-kernel@...r.kernel.org, akpm@...ux-foundation.org,
	bhelgaas@...gle.com, ilpo.jarvinen@...ux.intel.com,
	mika.westerberg@...ux.intel.com, ying.huang@...el.com,
	tglx@...utronix.de, takahiro.akashi@...aro.org,
	stable@...r.kernel.org
Subject: Re: [PATCH] resource,kexec: walk_system_ram_res_rev must retain
 resource flags

On Fri, Oct 18, 2024 at 09:52:47PM +0800, Baoquan He wrote:
> On 10/18/24 at 03:22pm, Andy Shevchenko wrote:
> > On Fri, Oct 18, 2024 at 10:18:42AM +0800, Baoquan He wrote:
> > > On 10/17/24 at 03:03pm, Gregory Price wrote:
> > > > walk_system_ram_res_rev() erroneously discards resource flags when
> > > > passing the information to the callback.
> > > > 
> > > > This causes systems with IORESOURCE_SYSRAM_DRIVER_MANAGED memory to
> > > > have these resources selected during kexec to store kexec buffers
> > > > if that memory happens to be at placed above normal system ram.
> > > 
> > > Sorry about that. I haven't checked IORESOURCE_SYSRAM_DRIVER_MANAGED
> > > memory carefully, wondering if res could be set as
> > > 'IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY' plus
> > > IORESOURCE_SYSRAM_DRIVER_MANAGED in iomem_resource tree.
> > > 
> > > Anyway, the change in this patch is certainly better. Thanks.
> > 
> > Can we get more test cases in the respective module, please?
> 
> Do you mean testing CXL memory in kexec/kdump? No, we can't. Kexec/kdump
> test cases basically is system testing, not unit test or module test. It
> needs run system and then jump to 2nd kernel, vm can be used but it
> can't cover many cases existing only on baremetal. Currenly, Redhat's
> CKI is heavily relied on to test them, however I am not sure if system
> with CXL support is available in our LAB.
> 
> Not sure if I got you right.

I meant since we touch resource.c, we should really touch resource_kunit.c
*in addition to*.

-- 
With Best Regards,
Andy Shevchenko