| 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
| ||
|
Message-ID:
<MN0PR21MB343793AB80403CBE9BE5EDFDCAA72@MN0PR21MB3437.namprd21.prod.outlook.com>
Date: Tue, 25 Mar 2025 18:11:24 +0000
From: Haiyang Zhang <haiyangz@...rosoft.com>
To: Long Li <longli@...rosoft.com>, "linux-hyperv@...r.kernel.org"
<linux-hyperv@...r.kernel.org>, "netdev@...r.kernel.org"
<netdev@...r.kernel.org>
CC: Dexuan Cui <decui@...rosoft.com>, "stephen@...workplumber.org"
<stephen@...workplumber.org>, KY Srinivasan <kys@...rosoft.com>, Paul
Rosswurm <paulros@...rosoft.com>, "olaf@...fle.de" <olaf@...fle.de>, vkuznets
<vkuznets@...hat.com>, "davem@...emloft.net" <davem@...emloft.net>,
"wei.liu@...nel.org" <wei.liu@...nel.org>, "edumazet@...gle.com"
<edumazet@...gle.com>, "kuba@...nel.org" <kuba@...nel.org>,
"pabeni@...hat.com" <pabeni@...hat.com>, "leon@...nel.org" <leon@...nel.org>,
"ssengar@...ux.microsoft.com" <ssengar@...ux.microsoft.com>,
"linux-rdma@...r.kernel.org" <linux-rdma@...r.kernel.org>,
"daniel@...earbox.net" <daniel@...earbox.net>, "john.fastabend@...il.com"
<john.fastabend@...il.com>, "bpf@...r.kernel.org" <bpf@...r.kernel.org>,
"ast@...nel.org" <ast@...nel.org>, "hawk@...nel.org" <hawk@...nel.org>,
"tglx@...utronix.de" <tglx@...utronix.de>, "shradhagupta@...ux.microsoft.com"
<shradhagupta@...ux.microsoft.com>, "jesse.brandeburg@...el.com"
<jesse.brandeburg@...el.com>, "andrew+netdev@...n.ch"
<andrew+netdev@...n.ch>, "linux-kernel@...r.kernel.org"
<linux-kernel@...r.kernel.org>, "stable@...r.kernel.org"
<stable@...r.kernel.org>
Subject: RE: [PATCH net,v2] net: mana: Switch to page pool for jumbo frames
> -----Original Message-----
> From: Long Li <longli@...rosoft.com>
> Sent: Tuesday, March 25, 2025 1:06 PM
> To: Haiyang Zhang <haiyangz@...rosoft.com>; linux-hyperv@...r.kernel.org;
> netdev@...r.kernel.org
> Cc: Dexuan Cui <decui@...rosoft.com>; stephen@...workplumber.org; KY
> Srinivasan <kys@...rosoft.com>; Paul Rosswurm <paulros@...rosoft.com>;
> olaf@...fle.de; vkuznets <vkuznets@...hat.com>; davem@...emloft.net;
> wei.liu@...nel.org; edumazet@...gle.com; kuba@...nel.org;
> pabeni@...hat.com; leon@...nel.org; ssengar@...ux.microsoft.com; linux-
> rdma@...r.kernel.org; daniel@...earbox.net; john.fastabend@...il.com;
> bpf@...r.kernel.org; ast@...nel.org; hawk@...nel.org; tglx@...utronix.de;
> shradhagupta@...ux.microsoft.com; jesse.brandeburg@...el.com;
> andrew+netdev@...n.ch; linux-kernel@...r.kernel.org;
> stable@...r.kernel.org
> Subject: RE: [PATCH net,v2] net: mana: Switch to page pool for jumbo
> frames
>
>
>
> > -----Original Message-----
> > From: LKML haiyangz <lkmlhyz@...rosoft.com> On Behalf Of Haiyang Zhang
> > Sent: Tuesday, March 25, 2025 9:33 AM
> > To: linux-hyperv@...r.kernel.org; netdev@...r.kernel.org
> > Cc: Haiyang Zhang <haiyangz@...rosoft.com>; Dexuan Cui
> > <decui@...rosoft.com>; stephen@...workplumber.org; KY Srinivasan
> > <kys@...rosoft.com>; Paul Rosswurm <paulros@...rosoft.com>;
> > olaf@...fle.de; vkuznets <vkuznets@...hat.com>; davem@...emloft.net;
> > wei.liu@...nel.org; edumazet@...gle.com; kuba@...nel.org;
> > pabeni@...hat.com; leon@...nel.org; Long Li <longli@...rosoft.com>;
> > ssengar@...ux.microsoft.com; linux-rdma@...r.kernel.org;
> > daniel@...earbox.net; john.fastabend@...il.com; bpf@...r.kernel.org;
> > ast@...nel.org; hawk@...nel.org; tglx@...utronix.de;
> > shradhagupta@...ux.microsoft.com; jesse.brandeburg@...el.com;
> > andrew+netdev@...n.ch; linux-kernel@...r.kernel.org;
> stable@...r.kernel.org
> > Subject: [PATCH net,v2] net: mana: Switch to page pool for jumbo frames
> >
> > Frag allocators, such as netdev_alloc_frag(), were not designed to work
> for
> > fragsz > PAGE_SIZE.
> >
> > So, switch to page pool for jumbo frames instead of using page frag
> allocators.
> > This driver is using page pool for smaller MTUs already.
> >
> > Cc: stable@...r.kernel.org
> > Fixes: 80f6215b450e ("net: mana: Add support for jumbo frame")
> > Signed-off-by: Haiyang Zhang <haiyangz@...rosoft.com>
> > ---
> > v2: updated the commit msg as suggested by Jakub Kicinski.
> >
> > ---
> > drivers/net/ethernet/microsoft/mana/mana_en.c | 46 ++++---------------
> > 1 file changed, 9 insertions(+), 37 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c
> > b/drivers/net/ethernet/microsoft/mana/mana_en.c
> > index 9a8171f099b6..4d41f4cca3d8 100644
> > --- a/drivers/net/ethernet/microsoft/mana/mana_en.c
> > +++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
> > @@ -661,30 +661,16 @@ int mana_pre_alloc_rxbufs(struct mana_port_context
> > *mpc, int new_mtu, int num_qu
> > mpc->rxbpre_total = 0;
> >
> > for (i = 0; i < num_rxb; i++) {
> > - if (mpc->rxbpre_alloc_size > PAGE_SIZE) {
> > - va = netdev_alloc_frag(mpc->rxbpre_alloc_size);
> > - if (!va)
> > - goto error;
> > -
> > - page = virt_to_head_page(va);
> > - /* Check if the frag falls back to single page */
> > - if (compound_order(page) <
> > - get_order(mpc->rxbpre_alloc_size)) {
> > - put_page(page);
> > - goto error;
> > - }
> > - } else {
> > - page = dev_alloc_page();
> > - if (!page)
> > - goto error;
> > + page = dev_alloc_pages(get_order(mpc->rxbpre_alloc_size));
> > + if (!page)
> > + goto error;
> >
> > - va = page_to_virt(page);
> > - }
> > + va = page_to_virt(page);
> >
> > da = dma_map_single(dev, va + mpc->rxbpre_headroom,
> > mpc->rxbpre_datasize, DMA_FROM_DEVICE);
> > if (dma_mapping_error(dev, da)) {
> > - put_page(virt_to_head_page(va));
> > + put_page(page);
>
> Should we use __free_pages()?
Quote from doc: https://www.kernel.org/doc/html/next/core-api/mm-api.html
___free_pages():
"This function can free multi-page allocations that are not compound pages."
"If you want to use the page's reference count to decide when to free the
allocation, you should allocate a compound page, and use put_page() instead
of __free_pages()."
And, since dev_alloc_pages returns compound page for high order page, we
use put_page() which works for both compound & single page.
Thanks,
- Haiyang
Powered by blists - more mailing lists