From: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
To: Yinghai Lu <yinghai@kernel.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>,
Ingo Molnar <mingo@elte.hu>,
Linus Torvalds <torvalds@linux-foundation.org>,
"H. Peter Anvin" <hpa@zytor.com>,
Andrew Morton <akpm@linux-foundation.org>,
Thomas Gleixner <tglx@linutronix.de>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
linux-pci@vger.kernel.org, yannick.roehlly@free.fr
Subject: Re: [RFC PATCH 1/2] pci: don't assume pref memio are 64bit -v3
Date: Fri, 24 Apr 2009 02:19:36 +0400 [thread overview]
Message-ID: <20090423221936.GA24171@jurassic.park.msu.ru> (raw)
In-Reply-To: <49F08580.9050407@kernel.org>
On Thu, Apr 23, 2009 at 08:13:04AM -0700, Yinghai Lu wrote:
> at least the one in mm/memory_hotplug.c
>
> /* add this memory to iomem resource */
> static struct resource *register_memory_resource(u64 start, u64 size)
> {
> struct resource *res;
> res = kzalloc(sizeof(struct resource), GFP_KERNEL);
> BUG_ON(!res);
>
> res->name = "System RAM";
> res->start = start;
> res->end = start + size - 1;
> res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
> if (request_resource(&iomem_resource, res) < 0) {
> printk("System RAM resource %llx - %llx cannot be added\n",
> (unsigned long long)res->start, (unsigned long long)res->end);
> kfree(res);
> res = NULL;
> }
> return res;
> }
Indeed. It's a really strong argument against mem64 resource approach.
On the other hand, it shows that getting 64-bit allocations right is
indeed a very complex issue - without well defined root bus ranges
there is a high risk of unexpectedly breaking something, like that memory
hotplug. Oh well...
So if the main purpose is to prevent 32-bit allocations in the DAC
area, some mix of your v2 and v3 patches seems to be the way to go.
That is
- keep IORESOURCE_MEM_64 bits from -v3, but drop iomem32_resource
and iomem64_resource things;
- pass "max" argument to allocate_resource() like you did in -v2,
but *only* then allocating from iomem_resource (r == &iomem_resource).
Also, instead of max = 0xffffffff use something like max = PCIBIOS_MAX_MEM_32.
include/linux/pci.h:
#ifndef PCIBIOS_MAX_MEM_32
#define PCIBIOS_MAX_MEM_32 (-1)
#endif
This should preserve the current behaviour of pci_bus_alloc_resource()
on non-x86 arches; overridden in arch/x86/include/asm/pci.h:
#define PCIBIOS_MAX_MEM_32 0xffffffff
> check bits 0-3 and check PCI_PREF_BASE_UPPER32 register being r/w ?
Yes. If these bits are zero, no further checks are needed -
bridge is 32-bit. If they aren't, do additional check for
PCI_PREF_BASE_UPPER32 being non-zero or writable, but *only*
if this prefetch resource is not already allocated (res->parent == NULL),
just for safety reasons - we don't want to disconnect the allocated
range from the bus even for a short time.
Ivan.
next prev parent reply other threads:[~2009-04-23 22:19 UTC|newest]
Thread overview: 117+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <bug-11103-13546@http.bugzilla.kernel.org/>
[not found] ` <200904101913.n3AJDhMm018684@demeter.kernel.org>
2009-04-10 20:27 ` [Bug 11103] Can't use framebuffer or vesa Xorg with two memory modules Yinghai Lu
2009-04-11 3:29 ` Yinghai Lu
2009-04-14 20:49 ` [PATCH] pci: don't assume pref memio are 64bit -v2 Yinghai Lu
2009-04-14 20:50 ` [PATCH] x86/pci: make pci_mem_start to be aligned only Yinghai Lu
2009-04-14 21:10 ` Linus Torvalds
2009-04-14 21:27 ` H. Peter Anvin
2009-04-14 21:27 ` Yinghai Lu
2009-04-14 22:35 ` Yannick Roehlly
2009-04-15 0:29 ` [PATCH] x86/pci: make pci_mem_start to be aligned only -v2 Yinghai Lu
2009-04-15 0:41 ` [PATCH] x86/pci: make pci_mem_start to be aligned only -v3 Yinghai Lu
2009-04-15 0:42 ` [PATCH] x86/pci: fix -1 calling to e820_all_mapped with mmconfig Yinghai Lu
2009-04-16 16:31 ` [PATCH] x86/pci: make pci_mem_start to be aligned only -v3 Jesse Barnes
2009-04-16 16:44 ` Linus Torvalds
2009-04-16 16:56 ` Ingo Molnar
2009-04-16 17:18 ` Yinghai Lu
2009-04-16 17:27 ` H. Peter Anvin
2009-04-16 17:38 ` Ingo Molnar
2009-04-16 17:28 ` Ingo Molnar
2009-04-16 20:13 ` [PATCH] x86/pci: make pci_mem_start to be aligned only -v4 Yinghai Lu
2009-04-16 23:18 ` Linus Torvalds
2009-04-16 23:54 ` Ingo Molnar
2009-04-17 0:24 ` Linus Torvalds
2009-04-17 13:16 ` Ingo Molnar
2009-04-17 21:59 ` Yinghai Lu
2009-04-17 22:04 ` H. Peter Anvin
2009-04-18 5:37 ` [PATCH] pci: keep pci device resource name pointer right Yinghai Lu
2009-04-18 7:51 ` Ingo Molnar
2009-04-18 16:05 ` Jesse Barnes
2009-04-18 18:42 ` Linus Torvalds
2009-04-18 19:19 ` Yinghai Lu
2009-04-18 19:23 ` Greg KH
2009-04-18 20:00 ` Kay Sievers
2009-04-18 20:27 ` Kay Sievers
2009-04-18 20:37 ` Ingo Molnar
2009-04-18 22:05 ` [PATCH] driver: dont update dev_name via device_add path Yinghai Lu
2009-04-28 7:36 ` [PATCH] driver: make dev_set_name(, NULL) work Yinghai Lu
2009-04-28 7:42 ` [RFC PATCH] use dev_set_name(,NULL) to prevent leaking Yinghai Lu
2009-04-28 8:25 ` Kay Sievers
2009-04-28 15:21 ` Yinghai Lu
2009-04-28 15:34 ` Yinghai Lu
2009-04-28 15:39 ` Greg KH
2009-04-28 15:51 ` Yinghai Lu
2009-04-28 15:56 ` Kay Sievers
2009-04-28 16:08 ` Yinghai Lu
2009-04-28 16:15 ` Kay Sievers
2009-04-28 19:04 ` Yinghai Lu
2009-04-28 16:36 ` Yinghai Lu
2009-04-28 16:50 ` Kay Sievers
2009-04-28 14:52 ` Greg KH
2009-04-28 14:51 ` [PATCH] driver: make dev_set_name(, NULL) work Greg KH
2009-04-28 15:14 ` Yinghai Lu
2009-04-28 15:39 ` Greg KH
2009-04-18 21:07 ` [PATCH] pci: keep pci device resource name pointer right Yinghai Lu
2009-04-18 22:17 ` Linus Torvalds
2009-04-18 20:00 ` [PATCH] driver: dont update dev_name if it is not changed Yinghai Lu
2009-04-18 20:11 ` Ingo Molnar
2009-04-18 20:20 ` Yinghai Lu
2009-04-18 20:27 ` Ingo Molnar
2009-04-18 8:33 ` [PATCH] x86/pci: make pci_mem_start to be aligned only -v4 Yinghai Lu
2009-04-18 9:22 ` Ingo Molnar
2009-04-18 17:07 ` Yinghai Lu
2009-04-18 18:57 ` Linus Torvalds
2009-04-18 19:14 ` Ingo Molnar
2009-04-18 19:26 ` Yinghai Lu
2009-04-18 22:20 ` Yinghai Lu
2009-04-18 22:31 ` Linus Torvalds
2009-04-18 20:13 ` Ivan Kokshaysky
2009-04-18 18:50 ` Linus Torvalds
2009-04-18 22:44 ` Yinghai Lu
2009-04-18 23:01 ` Yinghai Lu
2009-04-18 23:06 ` Linus Torvalds
2009-04-18 23:26 ` Yinghai Lu
2009-04-18 23:30 ` Yinghai Lu
2009-04-18 23:04 ` Linus Torvalds
2009-04-19 0:32 ` H. Peter Anvin
2009-04-19 4:50 ` Linus Torvalds
2009-04-19 5:26 ` Yinghai Lu
2009-04-19 19:35 ` Yannick Roehlly
2009-04-19 19:59 ` Yinghai Lu
2009-04-19 20:24 ` Yannick Roehlly
2009-04-19 9:02 ` Ingo Molnar
2009-04-19 9:06 ` Ingo Molnar
2009-04-19 17:52 ` Jesse Barnes
2009-04-20 22:33 ` Ivan Kokshaysky
2009-04-20 22:52 ` Yinghai Lu
2009-04-21 10:54 ` Ivan Kokshaysky
2009-04-21 0:09 ` Yinghai Lu
2009-04-21 10:56 ` Ivan Kokshaysky
2009-04-21 15:57 ` Yinghai Lu
2009-04-22 22:37 ` [RFC PATCH 1/2] pci: don't assume pref memio are 64bit -v3 Yinghai Lu
2009-04-22 22:38 ` [RFC PATCH 2/2] pci: try to assign res for device under transparent bridges Yinghai Lu
2009-04-22 22:49 ` [RFC PATCH 1/2] pci: don't assume pref memio are 64bit -v3 Jesse Barnes
2009-04-23 0:49 ` Yinghai Lu
2009-04-23 1:05 ` Jesse Barnes
2009-04-23 2:03 ` Yinghai Lu
2009-04-23 12:58 ` Ivan Kokshaysky
2009-04-23 15:30 ` Yinghai Lu
2009-04-23 2:10 ` Yinghai Lu
2009-04-23 13:22 ` Ivan Kokshaysky
2009-04-23 15:13 ` Yinghai Lu
2009-04-23 22:19 ` Ivan Kokshaysky [this message]
2009-04-24 3:48 ` [PATCH 1/4] pci/x86: don't assume pref memio are 64bit -v4 Yinghai Lu
2009-04-24 3:49 ` [PATCH 2/4] pci: try to assign res for device under transparent bridges -v2 Yinghai Lu
2009-04-24 3:50 ` [PATCH 3/4] x86: reserve range near the ram Yinghai Lu
2009-04-24 3:50 ` [PATCH 4/4] x86/pci: make pci_mem_start to be aligned only -v5 Yinghai Lu
2009-04-24 13:16 ` [PATCH 1/4] pci/x86: don't assume pref memio are 64bit -v4 Ivan Kokshaysky
2009-05-05 18:52 ` Jesse Barnes
2009-05-06 12:33 ` Ingo Molnar
2009-05-06 15:06 ` [PATCH 1/2] x86: reserve range near the ram Yinghai Lu
2009-05-11 9:51 ` [tip:x86/mm] x86, e820, pci: reserve extra free space near end of RAM tip-bot for Linus Torvalds
2009-05-06 15:07 ` [PATCH 1/2] x86/pci: make pci_mem_start to be aligned only -v5 Yinghai Lu
2009-05-11 9:51 ` [tip:x86/mm] x86/pci: remove rounding quirk from e820_setup_gap() tip-bot for Yinghai Lu
2009-04-23 12:36 ` [RFC PATCH 1/2] pci: don't assume pref memio are 64bit -v3 Ivan Kokshaysky
2009-04-23 12:41 ` Ingo Molnar
2009-04-23 13:09 ` Ivan Kokshaysky
2009-04-23 15:05 ` Yinghai Lu
2009-04-21 15:41 ` [PATCH] x86/pci: make pci_mem_start to be aligned only -v4 Jesse Barnes
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20090423221936.GA24171@jurassic.park.msu.ru \
--to=ink@jurassic.park.msu.ru \
--cc=akpm@linux-foundation.org \
--cc=hpa@zytor.com \
--cc=jbarnes@virtuousgeek.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-pci@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=tglx@linutronix.de \
--cc=torvalds@linux-foundation.org \
--cc=yannick.roehlly@free.fr \
--cc=yinghai@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.