From: Ingo Molnar <mingo@elte.hu>
To: linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary
Date: Sun, 03 Jul 2011 19:46:18 +0000 [thread overview]
Message-ID: <20110703194618.GB27022@elte.hu> (raw)
In-Reply-To: <201107012244.57593.ptesarik@suse.cz>
* Petr Tesarik <ptesarik@suse.cz> wrote:
> > Do you expect distros to enable this boot option by default? I.e.
> > would SuSE be willing to ship with a restrictive /dev/mem by
> > default? That's really the wider goal we want to work towards.
>
> I'm not really the decision-maker on this, but even though I don't
> need it for crash, there are several other users which would have
> to be fixed:
>
> 1. hwinfo (EFI, MPTABLE and ACPI table parsing, analyzing video BIOS)
> 2. dmidecode (SMBIOS, DMI)
> 3. possibly others
But those tables wont be in regular RAM (they will be in ROM or in
RAM marked non-RAM in a special way in the e820 tables).
dmidecode certainly works on Fedora.
> > Hm, why would the ability "dirty and/or flush an arbitrary
> > physical cache line for testing purposes" be a DoS?
>
> Effectively switching off CPU caches can slow things down quite a
> bit... especially on a large SMP system. ;)
Flushing a cacheline isnt switching it off. You can already 'flush'
the cache from user-space as well, by trashing it for example. So i
don't see the DoS angle.
Thanks,
Ingo
next prev parent reply other threads:[~2011-07-03 19:46 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-17 8:38 [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-06-17 8:46 ` [PATCH 06/10] sh: change valid_phys_addr_range's @addr param to phys_addr_t Petr Tesarik
2011-06-17 9:30 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ingo Molnar
2011-06-17 9:41 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of Russell King - ARM Linux
2011-06-17 9:55 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-06-20 2:42 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Américo Wang
2011-06-27 7:46 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of Petr Tesarik
2011-06-19 23:02 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ryan Mallon
2011-06-19 23:44 ` H. Peter Anvin
2011-06-20 7:41 ` Ingo Molnar
2011-06-20 15:59 ` H. Peter Anvin
2011-06-20 16:40 ` Ingo Molnar
2011-06-20 16:44 ` H. Peter Anvin
2011-06-21 6:56 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of Srivatsa Vaddagiri
2011-06-20 0:42 ` Matthew Wilcox
2011-06-20 0:46 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ryan Mallon
2011-06-20 0:52 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of Matthew Wilcox
2011-06-20 1:02 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ryan Mallon
2011-06-20 7:31 ` Ingo Molnar
2011-06-20 8:03 ` Ryan Mallon
2011-06-20 17:10 ` Ray Lee
2011-06-29 9:05 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-07-01 12:58 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ingo Molnar
2011-07-01 13:43 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-07-01 13:47 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Christoph Hellwig
2011-07-01 14:37 ` Ingo Molnar
2011-07-01 14:41 ` Christoph Hellwig
2011-07-01 14:46 ` Ingo Molnar
2011-07-01 14:54 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-07-01 15:36 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ingo Molnar
2011-07-01 16:00 ` H. Peter Anvin
2011-07-01 16:13 ` Ingo Molnar
2011-07-01 19:34 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-07-01 19:56 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary Ingo Molnar
2011-07-01 20:44 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses Petr Tesarik
2011-07-03 19:46 ` Ingo Molnar [this message]
2011-07-05 17:49 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of Matthew Garrett
2011-07-05 17:56 ` [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary H. Peter Anvin
2011-07-05 22:34 ` H. Peter Anvin
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