* Re: [PATCH] dummy: do not create a link (dummy0) at module init by default
From: Stephen Hemminger @ 2011-01-17 16:56 UTC (permalink / raw)
To: David Ward; +Cc: netdev
In-Reply-To: <1295225393-5779-1-git-send-email-david.ward@ll.mit.edu>
On Sun, 16 Jan 2011 19:49:53 -0500
David Ward <david.ward@ll.mit.edu> wrote:
> When the dummy network driver is initialized with no parameters, a link
> is automatically created (named 'dummy0'). This is inconsistent with
> other virtual network drivers such as veth, macvlan, and macvtap, which
> do not create a link upon initialization.
>
> This also causes confusing behavior when sending an RTM_NEWLINK message
> for a dummy link, because the kernel will load the dummy network driver
> first if it has not already been loaded. When that occurs, the result
> is that two new links are actually created (or if IFLA_IFNAME is set to
> 'dummy0', the error EEXIST is returned). The following iproute command
> demonstrates this behavior:
>
> ip link add [ name dummy0 ] type dummy
>
> With this change, users who still want to have a link created when the
> dummy network driver is loaded (instead of using iproute to create the
> link as shown above) just need to set the 'numdummies' parameter to 1:
>
> modprobe dummy numdummies=1
>
> Signed-off-by: David Ward <david.ward@ll.mit.edu>
I understand what you are trying to do, and it makes sense.
But because of the history behind this it can't change.
We can't change existing API and break user scripts.
The 'ip link' command support is new (in last couple of years), and
the module parameter has been around since early days.
If you want to load module without any devices just use:
modprobe dummy numdummies=0
--
^ permalink raw reply
* Re: [Patch] Kill off warning: ‘inline’ is not at beginning of declaration
From: Gustavo F. Padovan @ 2011-01-17 16:13 UTC (permalink / raw)
To: Jesper Juhl
Cc: alsa-devel, Mauro Carvalho Chehab, Takashi Iwai,
Frederic Weisbecker, H. Peter Anvin, Jaroslav Kysela, Jens Axboe,
Stephen Hemminger, Andi Kleen, Pekka Savola (ipv6), x86,
James Morris, Ingo Molnar, oprofile-list, Alexey Kuznetsov,
Mark Fasheh, Marcel Holtmann, John W. Linville, David Teigland,
Joel Becker, Thomas Gleixner, linux-edac, trivial,
Hideaki YOSHIFUJI, netdev, Greg
In-Reply-To: <alpine.LNX.2.00.1101170000270.13377@swampdragon.chaosbits.net>
* Jesper Juhl <jj@chaosbits.net> [2011-01-17 00:09:38 +0100]:
> Fix a bunch of
> warning: ‘inline’ is not at beginning of declaration
> messages when building a 'make allyesconfig' kernel with -Wextra.
>
> These warnings are trivial to kill, yet rather annoying when building with
> -Wextra.
> The more we can cut down on pointless crap like this the better (IMHO).
>
> A previous patch to do this for a 'allnoconfig' build has already been
> merged. This just takes the cleanup a little further.
>
> Signed-off-by: Jesper Juhl <jj@chaosbits.net>
> ---
> arch/x86/oprofile/op_model_p4.c | 2 +-
> drivers/bluetooth/btusb.c | 4 ++--
> drivers/cpuidle/sysfs.c | 2 +-
> drivers/edac/i7300_edac.c | 2 +-
> fs/ocfs2/dir.c | 2 +-
> kernel/trace/ring_buffer.c | 2 +-
> net/ipv6/inet6_hashtables.c | 2 +-
> net/mac80211/tx.c | 2 +-
> sound/pci/au88x0/au88x0.h | 4 ++--
> sound/pci/au88x0/au88x0_core.c | 4 ++--
> 10 files changed, 13 insertions(+), 13 deletions(-)
For drivers/bluetooth
Acked-by: Gustavo F. Padovan <padovan@profusion.mobi>
--
Gustavo F. Padovan
http://profusion.mobi
------------------------------------------------------------------------------
Protect Your Site and Customers from Malware Attacks
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malware threats, the impact they can have on your business, and how you
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^ permalink raw reply
* Re: 2.6.37 regression: adding main interface to a bridge breaks vlan interface RX
From: Ben Hutchings @ 2011-01-17 16:00 UTC (permalink / raw)
To: Simon Arlott; +Cc: netdev, Linux Kernel Mailing List, jesse, Herbert Xu
In-Reply-To: <4D32FC1C.3010905@simon.arlott.org.uk>
On Sun, 2011-01-16 at 14:09 +0000, Simon Arlott wrote:
> [ 1.666706] forcedeth 0000:00:08.0: ifname eth0, PHY OUI 0x5043 @ 16, addr 00:e0:81:4d:2b:ec
> [ 1.666767] forcedeth 0000:00:08.0: highdma csum vlan pwrctl mgmt gbit lnktim msi desc-v3
>
> I have eth0 and eth0.3840 which works until I add eth0 to a bridge.
> While eth0 is in a bridge (the bridge device is up), eth0.3840 is unable
> to receive packets. Using tcpdump on eth0 shows the packets being
> received with a VLAN tag but they don't appear on eth0.3840. They appear
> with the VLAN tag on the bridge interface.
[...]
This means the behaviour is now consistent, whether or not hardware VLAN
tag stripping is enabled. (I previously pointed out the inconsistent
behaviour in <http://thread.gmane.org/gmane.linux.network/149864>.) I
would consider this an improvement.
Ben.
--
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
^ permalink raw reply
* RE: [PATCH] USB CDC NCM: tx_fixup() race condition fix
From: Alexey ORISHKO @ 2011-01-17 15:04 UTC (permalink / raw)
To: Sergei Shtylyov
Cc: linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
davem-fT/PcQaiUtIeIZ0/mPfg9Q@public.gmane.org,
gregkh-l3A5Bk7waGM@public.gmane.org,
yauheni.kaliuta-xNZwKgViW5gAvxtiuMwx3w@public.gmane.org
In-Reply-To: <4D3458F7.5070209-hkdhdckH98+B+jHODAdFcQ@public.gmane.org>
> > - tx_fixup() call be called from either timer callback or from xmit()
>
> s/call/can/?
Yes :-)
>
> > in usbnet, so spinlock is added to avoid concurrency-related
> problem.
> > - minor correction due checkpatch warning for some line over 80 chars
>
> Due to?
yep
Sorry for typos...
Regards,
alexey
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^ permalink raw reply
* Re: [PATCH] USB CDC NCM: tx_fixup() race condition fix
From: Sergei Shtylyov @ 2011-01-17 14:57 UTC (permalink / raw)
To: Alexey Orishko
Cc: linux-usb-u79uwXL29TY76Z2rM5mHXA, netdev-u79uwXL29TY76Z2rM5mHXA,
davem-fT/PcQaiUtIeIZ0/mPfg9Q, gregkh-l3A5Bk7waGM,
yauheni.kaliuta-xNZwKgViW5gAvxtiuMwx3w, Alexey Orishko
In-Reply-To: <1295271573-8890-1-git-send-email-alexey.orishko-0IS4wlFg1OjSUeElwK9/Pw@public.gmane.org>
Hello.
Alexey Orishko wrote:
> - tx_fixup() call be called from either timer callback or from xmit()
s/call/can/?
> in usbnet, so spinlock is added to avoid concurrency-related problem.
> - minor correction due checkpatch warning for some line over 80 chars
Due to?
> after previous patch was applied.
> Signed-off-by: Alexey Orishko <alexey.orishko-0IS4wlFg1OjSUeElwK9/Pw@public.gmane.org>
> ---
> drivers/net/usb/cdc_ncm.c | 13 ++++++++-----
> 1 files changed, 8 insertions(+), 5 deletions(-)
> diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
> index d776c4a..bf13fa6 100644
> --- a/drivers/net/usb/cdc_ncm.c
> +++ b/drivers/net/usb/cdc_ncm.c
> @@ -54,7 +54,7 @@
> #include <linux/usb/usbnet.h>
> #include <linux/usb/cdc.h>
>
> -#define DRIVER_VERSION "30-Nov-2010"
> +#define DRIVER_VERSION "17-Jan-2011"
>
> /* CDC NCM subclass 3.2.1 */
> #define USB_CDC_NCM_NDP16_LENGTH_MIN 0x10
> @@ -873,9 +873,11 @@ static void cdc_ncm_tx_timeout(unsigned long arg)
>
> spin_unlock(&ctx->mtx);
>
> - if (restart)
> + if (restart) {
> + spin_lock(&ctx->mtx);
> cdc_ncm_tx_timeout_start(ctx);
> - else if (ctx->netdev != NULL)
> + spin_unlock(&ctx->mtx);
> + } else if (ctx->netdev != NULL)
The 'else' branch should now also have {}, according to
Documentation/CodingStyle.
> usbnet_start_xmit(NULL, ctx->netdev);
> }
>
> @@ -1021,7 +1024,7 @@ static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
> (temp > CDC_NCM_MAX_DATAGRAM_SIZE) || (temp < ETH_HLEN)) {
> pr_debug("invalid frame detected (ignored)"
> "offset[%u]=%u, length=%u, skb=%p\n",
> - x, offset, temp, skb_in);
> + x, offset, temp, skb_in);
Would be good to align uniformly with the previous line...
WBR, Sergei
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^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Jonas Gorski @ 2011-01-17 14:01 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Michael Büsch, linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <AANLkTinwGaqg8ahGWd3+_dfhrCNTQNOfO1E-EUepFJ+C-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
On 17 January 2011 14:54, Geert Uytterhoeven <geert-Td1EMuHUCqxL1ZNQvxDV9g@public.gmane.org> wrote:
> If it's AMBA, can it be integrated with the existing code in drivers/amba/?
Hm, I once had a sentence about it there, I must have accidentally deleted it.
I tried finding similarities between Broadcom's code and ARM's AMBA
specification to better understand the code, but except some tiny ones
I couldn't find anything usable. Unfortunately I couldn't find
anything about Broadcom's AMBA implementation, except that it's "AMBA"
licensed from ARM.
Jonas
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^ permalink raw reply
* Re: [Patch] Kill off warning: ‘inline’ is not at beginning of declaration
From: John W. Linville @ 2011-01-17 13:55 UTC (permalink / raw)
To: Jesper Juhl
Cc: alsa-devel, Mauro Carvalho Chehab, Takashi Iwai,
Frederic Weisbecker, Gustavo F. Padovan, Jens Axboe,
Stephen Hemminger, Andi Kleen, H. Peter Anvin,
Pekka Savola (ipv6), Robert Richter, x86, James Morris,
Ingo Molnar, oprofile-list, Alexey Kuznetsov, Mark Fasheh,
Marcel Holtmann, David Teigland, Joel Becker, Thomas Gleixner,
linux-edac, trivial, Hideaki YOSHIFUJI, netdev, Greg
In-Reply-To: <alpine.LNX.2.00.1101170000270.13377@swampdragon.chaosbits.net>
On Mon, Jan 17, 2011 at 12:09:38AM +0100, Jesper Juhl wrote:
> Fix a bunch of
> warning: ‘inline’ is not at beginning of declaration
> messages when building a 'make allyesconfig' kernel with -Wextra.
>
> These warnings are trivial to kill, yet rather annoying when building with
> -Wextra.
> The more we can cut down on pointless crap like this the better (IMHO).
>
> A previous patch to do this for a 'allnoconfig' build has already been
> merged. This just takes the cleanup a little further.
>
> Signed-off-by: Jesper Juhl <jj@chaosbits.net>
> ---
> net/mac80211/tx.c | 2 +-
ack
--
John W. Linville Someday the world will need a hero, and you
linville@tuxdriver.com might be all we have. Be ready.
_______________________________________________
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http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Geert Uytterhoeven @ 2011-01-17 13:54 UTC (permalink / raw)
To: Jonas Gorski
Cc: Michael Büsch, linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <AANLkTims0DPfG+u9qynuuj_-0WjUr1nAGLuFz3k706T--JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
On Mon, Jan 17, 2011 at 14:43, Jonas Gorski <jonas.gorski-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> On 17 January 2011 12:57, Michael Büsch <mb-fseUSCV1ubazQB+pC5nmwQ@public.gmane.org> wrote:
>> Well... I don't really like the idea of running one driver and
>> subsystem implementation on completely distinct types of silicon.
>> We will end up with the same mess that broadcom ended up with in
>> their "SB" code (broadcom's SSB backplane implementation).
>> For example, in their code the driver calls pci_enable_device() and
>> related PCI functions, even if there is no PCI device at all. The calls
>> are magically re-routed to the actual SB backplane.
>> You'd have to do the same mess with SSB. Calling ssb_device_enable()
>> will mean "enable the SSB device", if the backplane is SSB, and will
>> mean "enable the HND/AI" device, if the backplane is HND/AI.
> P.S: Any suggestions for the name? Would be "ai" okay? Technically
> it's "AMBA Interconnect", but "amba" is already taken.
If it's AMBA, can it be integrated with the existing code in drivers/amba/?
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Jonas Gorski @ 2011-01-17 13:43 UTC (permalink / raw)
To: Michael Büsch; +Cc: linux-mips, linux-wireless, netdev
In-Reply-To: <1295265468.24530.23.camel@maggie>
On 17 January 2011 12:57, Michael Büsch <mb@bu3sch.de> wrote:
> Well... I don't really like the idea of running one driver and
> subsystem implementation on completely distinct types of silicon.
> We will end up with the same mess that broadcom ended up with in
> their "SB" code (broadcom's SSB backplane implementation).
> For example, in their code the driver calls pci_enable_device() and
> related PCI functions, even if there is no PCI device at all. The calls
> are magically re-routed to the actual SB backplane.
> You'd have to do the same mess with SSB. Calling ssb_device_enable()
> will mean "enable the SSB device", if the backplane is SSB, and will
> mean "enable the HND/AI" device, if the backplane is HND/AI.
It didn't strike me as that bad, but I also didn't look at any PCI code.
> So I'm still in favor of doing a separate HND/AI bus implementation,
> even if
> that means duplicating a few lines of code.
Well, it means at least duplicating most of the chipcommon driver and
the mips core driver. But if you are fine with that, I see no problem
with having a separate driver for the AI bus.
> SSB doesn't search for SSB busses in the system, because there's no
> way to do so. The architecture (or the PCI/PCMCIA/SDIO device) registers
> the bus,
> if it detected an SSB device. So for the embedded case, it's hardcoded
> in the arch code. For the PCI case it simply depends on the PCI IDs.
> I don't see a problem here. Your arch code will already have to know
> what machine it is running on. So it will have to decide whether to
> register a SSB or HND/AI bus.
Okay. This is mostly for the embedded case, where it is possible to
create a single kernel that boots on both. The "detection" could also
be done through the cpu type (74k => register AI bus, else SSB bus)
instead of the chipid register of the common core.
>> Also I don't know
>> if it is a good idea to let arch-specific code depend on code in
>> staging.
>
> Sure. The code needs to be cleaned up and moved to the mainline kernel
> _anyway_. You don't get around this.
Yes, you are right.
So I guess the proposed course of action would be:
1. Make the HND/AI-Bus code from brcm80211 its own independent driver,
2. Re-add the non-wifi related code (chipcommon, mips, etc),
3. Clean up the code until it meets Linux' code style/quality,
4. Move it out of staging,
and finally
5. Add the required arch specific code to bcm47xx for the newer SoCs.
Jonas
P.S: Any suggestions for the name? Would be "ai" okay? Technically
it's "AMBA Interconnect", but "amba" is already taken.
^ permalink raw reply
* [PATCH] USB CDC NCM: tx_fixup() race condition fix
From: Alexey Orishko @ 2011-01-17 13:39 UTC (permalink / raw)
To: linux-usb-u79uwXL29TY76Z2rM5mHXA
Cc: netdev-u79uwXL29TY76Z2rM5mHXA, davem-fT/PcQaiUtIeIZ0/mPfg9Q,
gregkh-l3A5Bk7waGM, yauheni.kaliuta-xNZwKgViW5gAvxtiuMwx3w,
Alexey Orishko
- tx_fixup() call be called from either timer callback or from xmit()
in usbnet, so spinlock is added to avoid concurrency-related problem.
- minor correction due checkpatch warning for some line over 80 chars
after previous patch was applied.
Signed-off-by: Alexey Orishko <alexey.orishko-0IS4wlFg1OjSUeElwK9/Pw@public.gmane.org>
---
drivers/net/usb/cdc_ncm.c | 13 ++++++++-----
1 files changed, 8 insertions(+), 5 deletions(-)
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c
index d776c4a..bf13fa6 100644
--- a/drivers/net/usb/cdc_ncm.c
+++ b/drivers/net/usb/cdc_ncm.c
@@ -54,7 +54,7 @@
#include <linux/usb/usbnet.h>
#include <linux/usb/cdc.h>
-#define DRIVER_VERSION "30-Nov-2010"
+#define DRIVER_VERSION "17-Jan-2011"
/* CDC NCM subclass 3.2.1 */
#define USB_CDC_NCM_NDP16_LENGTH_MIN 0x10
@@ -873,9 +873,11 @@ static void cdc_ncm_tx_timeout(unsigned long arg)
spin_unlock(&ctx->mtx);
- if (restart)
+ if (restart) {
+ spin_lock(&ctx->mtx);
cdc_ncm_tx_timeout_start(ctx);
- else if (ctx->netdev != NULL)
+ spin_unlock(&ctx->mtx);
+ } else if (ctx->netdev != NULL)
usbnet_start_xmit(NULL, ctx->netdev);
}
@@ -900,7 +902,6 @@ cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
skb_out = cdc_ncm_fill_tx_frame(ctx, skb);
if (ctx->tx_curr_skb != NULL)
need_timer = 1;
- spin_unlock(&ctx->mtx);
/* Start timer, if there is a remaining skb */
if (need_timer)
@@ -908,6 +909,8 @@ cdc_ncm_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
if (skb_out)
dev->net->stats.tx_packets += ctx->tx_curr_frame_num;
+
+ spin_unlock(&ctx->mtx);
return skb_out;
error:
@@ -1021,7 +1024,7 @@ static int cdc_ncm_rx_fixup(struct usbnet *dev, struct sk_buff *skb_in)
(temp > CDC_NCM_MAX_DATAGRAM_SIZE) || (temp < ETH_HLEN)) {
pr_debug("invalid frame detected (ignored)"
"offset[%u]=%u, length=%u, skb=%p\n",
- x, offset, temp, skb_in);
+ x, offset, temp, skb_in);
if (!x)
goto error;
break;
--
1.7.0.4
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^ permalink raw reply related
* Re: rps testing questions
From: Ben Hutchings @ 2011-01-17 13:08 UTC (permalink / raw)
To: mi wake; +Cc: netdev
In-Reply-To: <AANLkTin1pC=auiFBt83YomdhVgUO8uSdvq=tPaDu0=3U@mail.gmail.com>
On Mon, 2011-01-17 at 17:43 +0800, mi wake wrote:
> I do a rps(Receive Packet Steering) testing on centos 5.5 with kernel 2.6.37.
> cpu: 8 core Intel.
> ethernet adapter: bnx2x
>
> Problem statement:
> enable rps with:
> echo "ff" > /sys/class/net/eth2/queues/rx-0/rps_cpus.
>
> running 1 instances of netperf TCP_RR: netperf -t TCP_RR -H 192.168.0.1 -c -C
> without rps: 9963.48(Trans Rate per sec)
> with rps: 9387.59(Trans Rate per sec)
>
> I do ab and tbench testing also find there is less tps with enable
> rps.but,there is more cpu using when with enable rps.when with enable
> rps ，softirqs is blanced on cpus.
>
> is there something wrong with my test？
In addition to what Eric said, check the interrupt moderation settings
(ethtool -c/-C options). One-way latency for a single request/response
test will be at least the interrupt moderation value.
I haven't tested RPS by itself (Solarflare NICs have plenty of hardware
queues) so I don't know whether it can improve latency. However, RFS
certainly does when there are many flows.
Ben.
--
Ben Hutchings, Senior Software Engineer, Solarflare Communications
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.
^ permalink raw reply
* Re: [PATCH v3 00/16] make rpc_pipefs be mountable multiple time
From: Rob Landley @ 2011-01-17 12:30 UTC (permalink / raw)
To: Kirill A. Shutemov
Cc: Trond Myklebust, J. Bruce Fields, Neil Brown, Pavel Emelyanov,
linux-nfs, David S. Miller, Al Viro, containers, netdev,
linux-kernel
In-Reply-To: <1295012954-7769-1-git-send-email-kas@openvz.org>
On 01/14/2011 07:48 AM, Kirill A. Shutemov wrote:
> Prepare nfs/sunrpc stack to use multiple instances of rpc_pipefs.
> Only for client for now.
Ok, Google is being really unhelpful here.
What is rpc_pipefs for? What uses it, and to do what exactly? Is it
used by nfs server code, or by the client code, or both? Is it a way
for userspace to talk to the kernel, or for the kernel to talk to
itself? Is it used at mount time, or during filesystem operation?
I'm interested in giving this patch series a much more thorough review,
but I can't figure out what the subsystem it's modifying actually _is_.
(Maybe this is something to do with filesystems/nfs/rpc-cache.txt?)
Rob
^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Michael Büsch @ 2011-01-17 12:00 UTC (permalink / raw)
To: Florian Fainelli
Cc: Jonas Gorski, linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <201101171220.52292.florian-p3rKhJxN3npAfugRpC6u6w@public.gmane.org>
On Mon, 2011-01-17 at 12:20 +0100, Florian Fainelli wrote:
> On Monday 17 January 2011 11:56:23 Michael Büsch wrote:
> > On Mon, 2011-01-17 at 11:46 +0100, Jonas Gorski wrote:
> > > Hello,
> > >
> > > I am currently looking into adding support for the newer Broadcom
> > > BCM47xx/53xx SoCs. They require having HND/AI support, which probably
> > > means merging the current SSB code and the HND/AI code from the
> > > brcm80211 driver. Is anyone already working on this?
> > >
> > > As far as I can see, there are two possibilities:
> > >
> > > a) Merge the HND/AI code into the current SSB code, or
> > >
> > > b) add the missing code for SoCs to brcm80211 and replace the SSB code
> > > with it.
> >
> > Why can't we keep those two platforms separated?
>
> That is also what I am wondering about. Considering that previous BCM47xx
> platforms use a MIPS4k core and newer one use MIPS74k or later, you would not
> be able to build a single kernel for both which takes advantages of compile-
> time optimizations targetting MIPS74k. If this ist not a big concern, then
> let's target a single kernel.
Ok, but it should be easily possible to compile both SSB and HND/AI
bus support into one kernel anyway. Nothing prevents drivers from having
an SSB and an HND/AI probe callback.
--
Greetings Michael.
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^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Michael Büsch @ 2011-01-17 11:57 UTC (permalink / raw)
To: Jonas Gorski
Cc: linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <AANLkTikJcug7LUTgX_YDD4Z8ZBrdkAdLq8_Epa6TkA5f-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
On Mon, 2011-01-17 at 12:21 +0100, Jonas Gorski wrote:
> On 17 January 2011 11:56, Michael Büsch <mb-fseUSCV1ubazQB+pC5nmwQ@public.gmane.org> wrote:
> > On Mon, 2011-01-17 at 11:46 +0100, Jonas Gorski wrote:
> >> a) Merge the HND/AI code into the current SSB code, or
> >>
> >> b) add the missing code for SoCs to brcm80211 and replace the SSB code with it.
> >
> > Why can't we keep those two platforms separated?
> > Is there really a lot of shared code between SSB and HND/AI?
>
> Yes, as far as I understand the AI bus behaves mostly like a SSB bus
> except for places like enabling/disabling cores. E.g. the AI bus also
> has a common core, which has a bit for telling whether its a SSB or AI
> bus, and has the mostly the same registers as the SSB common cores (so
> most driver_chipcommon_* stuff also applies for the AI bus).
Well... I don't really like the idea of running one driver and
subsystem implementation on completely distinct types of silicon.
We will end up with the same mess that broadcom ended up with in
their "SB" code (broadcom's SSB backplane implementation).
For example, in their code the driver calls pci_enable_device() and
related PCI functions, even if there is no PCI device at all. The calls
are magically re-routed to the actual SB backplane.
You'd have to do the same mess with SSB. Calling ssb_device_enable()
will mean "enable the SSB device", if the backplane is SSB, and will
mean "enable the HND/AI" device, if the backplane is HND/AI.
So I'm still in favor of doing a separate HND/AI bus implementation,
even if
that means duplicating a few lines of code. I think that compared to the
workarounds and conditionals needed for getting SSB to run on HND/AI
hardware, it will be a net win.
> > So why do we need to replace or merge SSB in the first place? Can't
> > it co-exist with HND/AI?
>
> It probably can, but then the SSB code must be at least made AI aware
> so it doesn't try to attach itself if it finds one.
SSB doesn't search for SSB busses in the system, because there's no
way to do so. The architecture (or the PCI/PCMCIA/SDIO device) registers
the bus,
if it detected an SSB device. So for the embedded case, it's hardcoded
in the arch code. For the PCI case it simply depends on the PCI IDs.
I don't see a problem here. Your arch code will already have to know
what machine it is running on. So it will have to decide whether to
register a SSB or HND/AI bus.
It's like a platform_device. However, it doesn't use the platform_device
mechanism. There's no technical reason. It would be trivial to port the
SSB bus registration to use platform_device, however.
> Also I don't know
> if it is a good idea to let arch-specific code depend on code in
> staging.
Sure. The code needs to be cleaned up and moved to the mainline kernel
_anyway_. You don't get around this.
--
Greetings Michael.
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^ permalink raw reply
* Re: [PATCH v4 05/10] net/fec: add dual fec support for mx28
From: Shawn Guo @ 2011-01-17 11:52 UTC (permalink / raw)
To: Lothar Waßmann
Cc: Uwe Kleine-König, gerg, B32542, netdev, s.hauer, jamie,
baruch, w.sang, r64343, eric, bryan.wu, jamie, davem,
linux-arm-kernel
In-Reply-To: <19763.64214.220441.325208@ipc1.ka-ro>
Hi Lothar,
On Mon, Jan 17, 2011 at 09:16:22AM +0100, Lothar Waßmann wrote:
> Hi,
>
> Shawn Guo writes:
> > On Fri, Jan 14, 2011 at 08:52:23AM +0100, Uwe Kleine-König wrote:
> > > On Fri, Jan 14, 2011 at 01:48:40PM +0800, Shawn Guo wrote:
> > > > Hi Uwe,
> > > >
> > > > On Thu, Jan 13, 2011 at 03:48:05PM +0100, Uwe Kleine-König wrote:
> > > >
> > > > [...]
> > > >
> > > > > > +/* Controller is ENET-MAC */
> > > > > > +#define FEC_QUIRK_ENET_MAC (1 << 0)
> > > > > does this really qualify to be a quirk?
> > > > >
> > > > My understanding is that ENET-MAC is a type of "quirky" FEC
> > > > controller.
> > > >
> > > > > > +/* Controller needs driver to swap frame */
> > > > > > +#define FEC_QUIRK_SWAP_FRAME (1 << 1)
> > > > > IMHO this is a bit misnamed. FEC_QUIRK_NEEDS_BE_DATA or similar would
> > > > > be more accurate.
> > > > >
> > > > When your make this change, you may want to pick a better name for
> > > > function swap_buffer too.
> > > >
> > > > [...]
> > > >
> > > > > > +static void *swap_buffer(void *bufaddr, int len)
> > > > > > +{
> > > > > > + int i;
> > > > > > + unsigned int *buf = bufaddr;
> > > > > > +
> > > > > > + for (i = 0; i < (len + 3) / 4; i++, buf++)
> > > > > > + *buf = cpu_to_be32(*buf);
> > > > > if len isn't a multiple of 4 this accesses bytes behind len. Is this
> > > > > generally OK here? (E.g. because skbs always have a length that is a
> > > > > multiple of 4?)
> > > > The len may not be a multiple of 4. But I believe bufaddr is always
> > > > a buffer allocated in a length that is a multiple of 4, and the 1~3
> > > > bytes exceeding the len very likely has no data that matters. But
> > > > yes, it deserves a safer implementation.
> > > Did you test what happens if bufaddr isn't aligned? Does it work at all
> > > then?
> > >
> > I see many calls passing a len that is not a multiple of 4, but it
> > works good.
> >
> That does not prove anything, actually.
>
> Anyway "bufaddr isn't aligned" != "len is not a multiple of 4".
> Is there any guarantee that the function cannot be called with a
> non-aligned buffer address?
>
Oops, I misunderstood the comment. With bounce buffer alignment
handling removed, the driver stops working. But at least, mx28
fec driver can work with FEC_ALIGNMENT 0x3 and not necessarily with
0xf.
I hope this is what you intended to know.
--
Regards,
Shawn
^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Jonas Gorski @ 2011-01-17 11:21 UTC (permalink / raw)
To: Michael Büsch
Cc: linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <1295261783.24530.3.camel@maggie>
On 17 January 2011 11:56, Michael Büsch <mb-fseUSCV1ubazQB+pC5nmwQ@public.gmane.org> wrote:
> On Mon, 2011-01-17 at 11:46 +0100, Jonas Gorski wrote:
>> a) Merge the HND/AI code into the current SSB code, or
>>
>> b) add the missing code for SoCs to brcm80211 and replace the SSB code with it.
>
> Why can't we keep those two platforms separated?
> Is there really a lot of shared code between SSB and HND/AI?
Yes, as far as I understand the AI bus behaves mostly like a SSB bus
except for places like enabling/disabling cores. E.g. the AI bus also
has a common core, which has a bit for telling whether its a SSB or AI
bus, and has the mostly the same registers as the SSB common cores (so
most driver_chipcommon_* stuff also applies for the AI bus).
> It's true that there's currently a lot of device functionality built
> into ssb. Like pci bridge, mips core, extif, etc...
> If you take all that code out, you're probably not left with anything.
That's because most shared code isn't in brcm80211, but only found in
the SDKs for the SoCs.
> So why do we need to replace or merge SSB in the first place? Can't
> it co-exist with HND/AI?
It probably can, but then the SSB code must be at least made AI aware
so it doesn't try to attach itself if it finds one. Also I don't know
if it is a good idea to let arch-specific code depend on code in
staging.
Jonas
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^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Florian Fainelli @ 2011-01-17 11:20 UTC (permalink / raw)
To: Michael Büsch
Cc: Jonas Gorski, linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <1295261783.24530.3.camel@maggie>
On Monday 17 January 2011 11:56:23 Michael Büsch wrote:
> On Mon, 2011-01-17 at 11:46 +0100, Jonas Gorski wrote:
> > Hello,
> >
> > I am currently looking into adding support for the newer Broadcom
> > BCM47xx/53xx SoCs. They require having HND/AI support, which probably
> > means merging the current SSB code and the HND/AI code from the
> > brcm80211 driver. Is anyone already working on this?
> >
> > As far as I can see, there are two possibilities:
> >
> > a) Merge the HND/AI code into the current SSB code, or
> >
> > b) add the missing code for SoCs to brcm80211 and replace the SSB code
> > with it.
>
> Why can't we keep those two platforms separated?
That is also what I am wondering about. Considering that previous BCM47xx
platforms use a MIPS4k core and newer one use MIPS74k or later, you would not
be able to build a single kernel for both which takes advantages of compile-
time optimizations targetting MIPS74k. If this ist not a big concern, then
let's target a single kernel.
> Is there really a lot of shared code between SSB and HND/AI?
>
> It's true that there's currently a lot of device functionality built
> into ssb. Like pci bridge, mips core, extif, etc...
> If you take all that code out, you're probably not left with anything.
>
> So why do we need to replace or merge SSB in the first place? Can't
> it co-exist with HND/AI?
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^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Michael Büsch @ 2011-01-17 11:17 UTC (permalink / raw)
To: Johannes Berg; +Cc: Jonas Gorski, linux-mips, linux-wireless, netdev
In-Reply-To: <1295262781.3726.6.camel@jlt3.sipsolutions.net>
On Mon, 2011-01-17 at 12:13 +0100, Johannes Berg wrote:
> On Mon, 2011-01-17 at 11:56 +0100, Michael Büsch wrote:
>
> > > As far as I can see, there are two possibilities:
> > >
> > > a) Merge the HND/AI code into the current SSB code, or
> > >
> > > b) add the missing code for SoCs to brcm80211 and replace the SSB code with it.
> >
> > Why can't we keep those two platforms separated?
> > Is there really a lot of shared code between SSB and HND/AI?
>
> I don't think there's a lot of shared code, but I believe that you need
> b43 to be able to target cores on both? And b43 currently uses the SSB
> APIs only.
Yeah right. That's what I was thinking about, too. Just leave SSB alone
and add bus glues to b43 for HND/AI. There's almost no SSB specific code
in b43. So it should be easily possible to add another probe entry from
the (to be written or derived from brcm80211) HND/AI subsystem.
--
Greetings Michael.
^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Johannes Berg @ 2011-01-17 11:13 UTC (permalink / raw)
To: Michael Büsch
Cc: Jonas Gorski, linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <1295261783.24530.3.camel@maggie>
On Mon, 2011-01-17 at 11:56 +0100, Michael Büsch wrote:
> > As far as I can see, there are two possibilities:
> >
> > a) Merge the HND/AI code into the current SSB code, or
> >
> > b) add the missing code for SoCs to brcm80211 and replace the SSB code with it.
>
> Why can't we keep those two platforms separated?
> Is there really a lot of shared code between SSB and HND/AI?
I don't think there's a lot of shared code, but I believe that you need
b43 to be able to target cores on both? And b43 currently uses the SSB
APIs only.
johannes
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^ permalink raw reply
* Re: Merging SSB and HND/AI support
From: Michael Büsch @ 2011-01-17 10:56 UTC (permalink / raw)
To: Jonas Gorski
Cc: linux-mips-6z/3iImG2C8G8FEW9MqTrA,
linux-wireless-u79uwXL29TY76Z2rM5mHXA,
netdev-u79uwXL29TY76Z2rM5mHXA
In-Reply-To: <AANLkTi=GDcy50zsC6=Dgv1-Ty3cYK2qpx9o=q3JdXuCh-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
On Mon, 2011-01-17 at 11:46 +0100, Jonas Gorski wrote:
> Hello,
>
> I am currently looking into adding support for the newer Broadcom
> BCM47xx/53xx SoCs. They require having HND/AI support, which probably
> means merging the current SSB code and the HND/AI code from the
> brcm80211 driver. Is anyone already working on this?
>
> As far as I can see, there are two possibilities:
>
> a) Merge the HND/AI code into the current SSB code, or
>
> b) add the missing code for SoCs to brcm80211 and replace the SSB code with it.
Why can't we keep those two platforms separated?
Is there really a lot of shared code between SSB and HND/AI?
It's true that there's currently a lot of device functionality built
into ssb. Like pci bridge, mips core, extif, etc...
If you take all that code out, you're probably not left with anything.
So why do we need to replace or merge SSB in the first place? Can't
it co-exist with HND/AI?
--
Greetings Michael.
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^ permalink raw reply
* Merging SSB and HND/AI support
From: Jonas Gorski @ 2011-01-17 10:46 UTC (permalink / raw)
To: Michael Buesch, linux-mips, linux-wireless, netdev
Hello,
I am currently looking into adding support for the newer Broadcom
BCM47xx/53xx SoCs. They require having HND/AI support, which probably
means merging the current SSB code and the HND/AI code from the
brcm80211 driver. Is anyone already working on this?
As far as I can see, there are two possibilities:
a) Merge the HND/AI code into the current SSB code, or
b) add the missing code for SoCs to brcm80211 and replace the SSB code with it.
The former is probably the less intrusive one, but requires a bit of
ssb-named-but-actually-not-ssb code unless one renames several
functions and structs.
The latter has the advantage of having a certain bus abstraction
already built-in, but would require adapting the b43 code to it. It
also looks like it doesn't support (very) old SoCs.
Regards,
Jonas
P.S: The Maintainers file says SSB's list is netdev, but I would have
expected it to be linux-wireless. Is this still correct?
^ permalink raw reply
* Re: Flow Control and Port Mirroring Revisited
From: Michael S. Tsirkin @ 2011-01-17 10:38 UTC (permalink / raw)
To: Rusty Russell
Cc: Simon Horman, Jesse Gross, Eric Dumazet, virtualization, dev,
virtualization, netdev, kvm
In-Reply-To: <201101171026.26213.rusty@rustcorp.com.au>
On Mon, Jan 17, 2011 at 10:26:25AM +1030, Rusty Russell wrote:
> On Mon, 17 Jan 2011 09:07:30 am Simon Horman wrote:
>
> [snip]
>
> I've been away, but what concerns me is that socket buffer limits are
> bypassed in various configurations, due to skb cloning. We should probably
> drop such limits altogether, or fix them to be consistent.
Further, it looks like when the limits are not bypassed, they
easily result in deadlocks. For example, with
multiple tun devices attached to a single bridge in host,
if a number of these have their queues blocked,
others will reach the socket buffer limit and
traffic on the bridge will get blocked altogether.
It might be better to drop the limits altogether
unless we can fix them. Happily, as the limits are off by
default, doing so does not require kernel changes.
> Simple fix is as someone suggested here, to attach the clone. That might
> seriously reduce your sk limit, though. I haven't thought about it hard,
> but might it make sense to move ownership into skb_shared_info; ie. the
> data, rather than the skb head?
>
> Cheers,
> Rusty.
tracking data ownership might benefit others such as various zero-copy
strategies. It might need to be done per-page, though, not per-skb.
--
MST
^ permalink raw reply
* Re: [PATCH] net: bluetooth: fix locking problem
From: Andrei Emeltchenko @ 2011-01-17 10:28 UTC (permalink / raw)
To: Vasiliy Kulikov
Cc: kernel-janitors, Marcel Holtmann, Gustavo F. Padovan,
David S. Miller, linux-bluetooth, netdev, linux-kernel
In-Reply-To: <1295258917-31092-1-git-send-email-segoon@openwall.com>
On Mon, Jan 17, 2011 at 12:08 PM, Vasiliy Kulikov <segoon@openwall.com> wrote:
> If alloc_skb() failed we still hold hci_dev_list_lock. The code should
> unlock it before exit.
>
> Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
> ---
> Compile tested only.
>
> net/bluetooth/mgmt.c | 4 +++-
> 1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
> index f827fd9..ace8726 100644
> --- a/net/bluetooth/mgmt.c
> +++ b/net/bluetooth/mgmt.c
> @@ -111,8 +111,10 @@ static int read_index_list(struct sock *sk)
>
> body_len = sizeof(*ev) + sizeof(*rp) + (2 * count);
> skb = alloc_skb(sizeof(*hdr) + body_len, GFP_ATOMIC);
> - if (!skb)
> + if (!skb) {
> + read_unlock(&hci_dev_list_lock);
> return -ENOMEM;
> + }
patch was send already on weekend
>
> hdr = (void *) skb_put(skb, sizeof(*hdr));
> hdr->opcode = cpu_to_le16(MGMT_EV_CMD_COMPLETE);
> --
> 1.7.0.4
>
> --
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> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>
^ permalink raw reply
* Re: Flow Control and Port Mirroring Revisited
From: Michael S. Tsirkin @ 2011-01-17 10:26 UTC (permalink / raw)
To: Simon Horman
Cc: Jesse Gross, Eric Dumazet, Rusty Russell, virtualization, dev,
virtualization, netdev, kvm
In-Reply-To: <20110116223728.GA6279@verge.net.au>
On Mon, Jan 17, 2011 at 07:37:30AM +0900, Simon Horman wrote:
> On Fri, Jan 14, 2011 at 08:54:15AM +0200, Michael S. Tsirkin wrote:
> > On Fri, Jan 14, 2011 at 03:35:28PM +0900, Simon Horman wrote:
> > > On Fri, Jan 14, 2011 at 06:58:18AM +0200, Michael S. Tsirkin wrote:
> > > > On Fri, Jan 14, 2011 at 08:41:36AM +0900, Simon Horman wrote:
> > > > > On Thu, Jan 13, 2011 at 10:45:38AM -0500, Jesse Gross wrote:
> > > > > > On Thu, Jan 13, 2011 at 1:47 AM, Simon Horman <horms@verge.net.au> wrote:
> > > > > > > On Mon, Jan 10, 2011 at 06:31:55PM +0900, Simon Horman wrote:
> > > > > > >> On Fri, Jan 07, 2011 at 10:23:58AM +0900, Simon Horman wrote:
> > > > > > >> > On Thu, Jan 06, 2011 at 05:38:01PM -0500, Jesse Gross wrote:
> > > > > > >> >
> > > > > > >> > [ snip ]
> > > > > > >> > >
> > > > > > >> > > I know that everyone likes a nice netperf result but I agree with
> > > > > > >> > > Michael that this probably isn't the right question to be asking. I
> > > > > > >> > > don't think that socket buffers are a real solution to the flow
> > > > > > >> > > control problem: they happen to provide that functionality but it's
> > > > > > >> > > more of a side effect than anything. It's just that the amount of
> > > > > > >> > > memory consumed by packets in the queue(s) doesn't really have any
> > > > > > >> > > implicit meaning for flow control (think multiple physical adapters,
> > > > > > >> > > all with the same speed instead of a virtual device and a physical
> > > > > > >> > > device with wildly different speeds). The analog in the physical
> > > > > > >> > > world that you're looking for would be Ethernet flow control.
> > > > > > >> > > Obviously, if the question is limiting CPU or memory consumption then
> > > > > > >> > > that's a different story.
> > > > > > >> >
> > > > > > >> > Point taken. I will see if I can control CPU (and thus memory) consumption
> > > > > > >> > using cgroups and/or tc.
> > > > > > >>
> > > > > > >> I have found that I can successfully control the throughput using
> > > > > > >> the following techniques
> > > > > > >>
> > > > > > >> 1) Place a tc egress filter on dummy0
> > > > > > >>
> > > > > > >> 2) Use ovs-ofctl to add a flow that sends skbs to dummy0 and then eth1,
> > > > > > >> this is effectively the same as one of my hacks to the datapath
> > > > > > >> that I mentioned in an earlier mail. The result is that eth1
> > > > > > >> "paces" the connection.
> > > >
> > > > This is actually a bug. This means that one slow connection will affect
> > > > fast ones. I intend to change the default for qemu to sndbuf=0 : this
> > > > will fix it but break your "pacing". So pls do not count on this
> > > > behaviour.
> > >
> > > Do you have a patch I could test?
> >
> > You can (and users already can) just run qemu with sndbuf=0. But if you
> > like, below.
>
> Thanks
>
> > > > > > > Further to this, I wonder if there is any interest in providing
> > > > > > > a method to switch the action order - using ovs-ofctl is a hack imho -
> > > > > > > and/or switching the default action order for mirroring.
> > > > > >
> > > > > > I'm not sure that there is a way to do this that is correct in the
> > > > > > generic case. It's possible that the destination could be a VM while
> > > > > > packets are being mirrored to a physical device or we could be
> > > > > > multicasting or some other arbitrarily complex scenario. Just think
> > > > > > of what a physical switch would do if it has ports with two different
> > > > > > speeds.
> > > > >
> > > > > Yes, I have considered that case. And I agree that perhaps there
> > > > > is no sensible default. But perhaps we could make it configurable somehow?
> > > >
> > > > The fix is at the application level. Run netperf with -b and -w flags to
> > > > limit the speed to a sensible value.
> > >
> > > Perhaps I should have stated my goals more clearly.
> > > I'm interested in situations where I don't control the application.
> >
> > Well an application that streams UDP without any throttling
> > at the application level will break on a physical network, right?
> > So I am not sure why should one try to make it work on the virtual one.
> >
> > But let's assume that you do want to throttle the guest
> > for reasons such as QOS. The proper approach seems
> > to be to throttle the sender, not have a dummy throttled
> > receiver "pacing" it. Place the qemu process in the
> > correct net_cls cgroup, set the class id and apply a rate limit?
>
> I would like to be able to use a class to rate limit egress packets.
> That much works fine for me.
>
> What I would also like is for there to be back-pressure such that the guest
> doesn't consume lots of CPU, spinning, sending packets as fast as it can,
> almost of all of which are dropped. That does seem like a lot of wasted
> CPU to me.
>
> Unfortunately there are several problems with this and I am fast concluding
> that I will need to use a CPU cgroup. Which does make some sense, as what I
> am really trying to limit here is CPU usage not network packet rates - even
> if the test using the CPU is netperf. So long as the CPU usage can
> (mostly) be attributed to the guest using a cgroup should work fine. And
> indeed seems to in my limited testing.
>
> One scenario in which I don't think it is possible for there to be
> back-pressure in a meaningful sense is if root in the guest sets
> /proc/sys/net/core/wmem_default to a large value, say 2000000.
>
>
> I do think that to some extent there is back-pressure provided by sockbuf
> in the case where process on the host is sending directly to a physical
> interface. And to my mind it would be "nice" if the same kind of
> back-pressure was present in guests. But through our discussions of the
> past week or so I get the feeling that is not your view of things.
It might be nice. Unfortunately this is not what we have implemented:
the sockbuf backpressure blocks the socket, what we have blocks all
transmit from the guest. Another issue is that the strategy we have
seems to be broken if the target is a guest on another machine.
So it won't be all that simple to implement well, and before we try,
I'd like to know whether there are applications that are helped
by it. For example, we could try to measure latency at various
pps and see whether the backpressure helps. netperf has -b, -w
flags which might help these measurements.
> Perhaps I could characterise the guest situation by saying:
> Egress packet rates can be controlled using tc on the host;
> Guest CPU usage can be controlled using CPU cgroups on the host;
> Sockbuf controls memory usage on the host;
Not really, the memory usage on the host is controlled by the
various queue lengths in the host. E.g. if you send packets to
the physical device, they will get queued there.
> Back-pressure is irrelevant.
Or at least, broken :)
--
MST
^ permalink raw reply
* [PATCH] net: bluetooth: fix locking problem
From: Vasiliy Kulikov @ 2011-01-17 10:08 UTC (permalink / raw)
To: kernel-janitors
Cc: Marcel Holtmann, Gustavo F. Padovan, David S. Miller,
linux-bluetooth, netdev, linux-kernel
If alloc_skb() failed we still hold hci_dev_list_lock. The code should
unlock it before exit.
Signed-off-by: Vasiliy Kulikov <segoon@openwall.com>
---
Compile tested only.
net/bluetooth/mgmt.c | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index f827fd9..ace8726 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -111,8 +111,10 @@ static int read_index_list(struct sock *sk)
body_len = sizeof(*ev) + sizeof(*rp) + (2 * count);
skb = alloc_skb(sizeof(*hdr) + body_len, GFP_ATOMIC);
- if (!skb)
+ if (!skb) {
+ read_unlock(&hci_dev_list_lock);
return -ENOMEM;
+ }
hdr = (void *) skb_put(skb, sizeof(*hdr));
hdr->opcode = cpu_to_le16(MGMT_EV_CMD_COMPLETE);
--
1.7.0.4
^ permalink raw reply related
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