From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 15 Nov 2021 13:53:24 +0200 From: Ilias Apalodimas Subject: Re: [PATCH net-next v6] page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA Message-ID: References: <20211013091920.1106-1-linyunsheng@huawei.com> <1090744a-3de6-1dc2-5efe-b7caae45223a@huawei.com> <644e10ca-87b8-b553-db96-984c0b2c6da1@collabora.com> <93173400-1d37-09ed-57ef-931550b5a582@huawei.com> MIME-Version: 1.0 In-Reply-To: <93173400-1d37-09ed-57ef-931550b5a582@huawei.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline List-ID: To: Yunsheng Lin Cc: Guillaume Tucker , davem@davemloft.net, kuba@kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linuxarm@openeuler.org, hawk@kernel.org, akpm@linux-foundation.org, peterz@infradead.org, will@kernel.org, jhubbard@nvidia.com, yuzhao@google.com, mcroce@microsoft.com, fenghua.yu@intel.com, feng.tang@intel.com, jgg@ziepe.ca, aarcange@redhat.com, guro@fb.com, "kernelci@groups.io" On Mon, Nov 15, 2021 at 11:34:59AM +0800, Yunsheng Lin wrote: > On 2021/11/12 17:21, Guillaume Tucker wrote: > > On 09/11/2021 12:02, Yunsheng Lin wrote: > >> On 2021/11/9 17:58, Guillaume Tucker wrote: > >>> Hi Yunsheng, > >>> > >>> Please see the bisection report below about a boot failure on > >>> rk3288-rock2-square which is pointing to this patch. The issue > >>> appears to only happen with CONFIG_ARM_LPAE=y. > >>> > >>> Reports aren't automatically sent to the public while we're > >>> trialing new bisection features on kernelci.org but this one > >>> looks valid. > >>> > >>> Some more details can be found here: > >>> > >>> https://linux.kernelci.org/test/case/id/6189968c3ec0a3c06e3358fe/ > >>> > >>> Here's the same revision on the same platform booting fine with a > >>> plain multi_v7_defconfig build: > >>> > >>> https://linux.kernelci.org/test/plan/id/61899d322c0e9fee7e3358ec/ > >>> > >>> Please let us know if you need any help debugging this issue or > >>> if you have a fix to try. > >> > >> The patch below is removing the dma mapping support in page pool > >> for 32 bit systems with 64 bit dma address, so it seems there > >> is indeed a a drvier using the the page pool with PP_FLAG_DMA_MAP > >> flags set in a 32 bit systems with 64 bit dma address. > >> > >> It seems we might need to revert the below patch or implement the > >> DMA-mapping tracking support in the driver as mentioned in the below > >> commit log. > >> > >> which ethernet driver do you use in your system? > > > > Thanks for taking a look and sorry for the slow reply. Here's a > > booting test job with LPAE disabled: > > > > https://linux.kernelci.org/test/plan/id/618dbb81c60c4d94503358f1/ > > https://storage.kernelci.org/mainline/master/v5.15-12452-g5833291ab6de/arm/multi_v7_defconfig/gcc-10/lab-collabora/baseline-nfs-rk3288-rock2-square.html#L812 > > > > [ 8.314523] rk_gmac-dwmac ff290000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx > > > > So the driver is drivers/net/ethernet/stmicro/stmmac/dwmac-rk.c > > Thanks for the report, this patch seems to cause problem for 32-bit > system with LPAE enabled. > > As LPAE seems like a common feature for 32 bits system, this patch > might need to be reverted. > > @Jesper, @Ilias, what do you think? So enabling LPAE also enables CONFIG_ARCH_DMA_ADDR_T_64BIT on that board? Doing a quick grep only selects that for XEN. I am ok reverting that, but I think we need to understand how the dma address ended up being 64bit. Regards /Ilias > > > > > Best wishes, > > Guillaume > > > > > >>> GitHub: https://github.com/kernelci/kernelci-project/issues/71 > >>> > >>> ------------------------------------------------------------------------------- > >>> > >>> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * > >>> * This automated bisection report was sent to you on the basis * > >>> * that you may be involved with the breaking commit it has * > >>> * found. No manual investigation has been done to verify it, * > >>> * and the root cause of the problem may be somewhere else. * > >>> * * > >>> * If you do send a fix, please include this trailer: * > >>> * Reported-by: "kernelci.org bot" * > >>> * * > >>> * Hope this helps! * > >>> * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * > >>> > >>> mainline/master bisection: baseline.login on rk3288-rock2-square > >>> > >>> Summary: > >>> Start: e851dfae4371d Merge tag 'kgdb-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux > >>> Plain log: https://storage.kernelci.org/mainline/master/v5.15-11387-ge851dfae4371/arm/multi_v7_defconfig+CONFIG_EFI=y+CONFIG_ARM_LPAE=y/gcc-10/lab-collabora/baseline-rk3288-rock2-square.txt > >>> HTML log: https://storage.kernelci.org/mainline/master/v5.15-11387-ge851dfae4371/arm/multi_v7_defconfig+CONFIG_EFI=y+CONFIG_ARM_LPAE=y/gcc-10/lab-collabora/baseline-rk3288-rock2-square.html > >>> Result: d00e60ee54b12 page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA > >>> > >>> Checks: > >>> revert: PASS > >>> verify: PASS > >>> > >>> Parameters: > >>> Tree: mainline > >>> URL: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > >>> Branch: master > >>> Target: rk3288-rock2-square > >>> CPU arch: arm > >>> Lab: lab-collabora > >>> Compiler: gcc-10 > >>> Config: multi_v7_defconfig+CONFIG_EFI=y+CONFIG_ARM_LPAE=y > >>> Test case: baseline.login > >>> > >>> Breaking commit found: > >>> > >>> ------------------------------------------------------------------------------- > >>> commit d00e60ee54b12de945b8493cf18c1ada9e422514 > >>> Author: Yunsheng Lin > >>> Date: Wed Oct 13 17:19:20 2021 +0800 > >>> > >>> page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA > >>> > >>> > >>> On 13/10/2021 10:19, Yunsheng Lin wrote: > >>>> As the 32-bit arch with 64-bit DMA seems to rare those days, > >>>> and page pool might carry a lot of code and complexity for > >>>> systems that possibly. > >>>> > >>>> So disable dma mapping support for such systems, if drivers > >>>> really want to work on such systems, they have to implement > >>>> their own DMA-mapping fallback tracking outside page_pool. > >>>> > >>>> Reviewed-by: Ilias Apalodimas > >>>> Signed-off-by: Yunsheng Lin > >>>> --- > >>>> V6: Drop pp page tracking support > >>>> --- > >>>> include/linux/mm_types.h | 13 +------------ > >>>> include/net/page_pool.h | 12 +----------- > >>>> net/core/page_pool.c | 10 ++++++---- > >>>> 3 files changed, 8 insertions(+), 27 deletions(-) > >>>> > >>>> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h > >>>> index 7f8ee09c711f..436e0946d691 100644 > >>>> --- a/include/linux/mm_types.h > >>>> +++ b/include/linux/mm_types.h > >>>> @@ -104,18 +104,7 @@ struct page { > >>>> struct page_pool *pp; > >>>> unsigned long _pp_mapping_pad; > >>>> unsigned long dma_addr; > >>>> - union { > >>>> - /** > >>>> - * dma_addr_upper: might require a 64-bit > >>>> - * value on 32-bit architectures. > >>>> - */ > >>>> - unsigned long dma_addr_upper; > >>>> - /** > >>>> - * For frag page support, not supported in > >>>> - * 32-bit architectures with 64-bit DMA. > >>>> - */ > >>>> - atomic_long_t pp_frag_count; > >>>> - }; > >>>> + atomic_long_t pp_frag_count; > >>>> }; > >>>> struct { /* slab, slob and slub */ > >>>> union { > >>>> diff --git a/include/net/page_pool.h b/include/net/page_pool.h > >>>> index a4082406a003..3855f069627f 100644 > >>>> --- a/include/net/page_pool.h > >>>> +++ b/include/net/page_pool.h > >>>> @@ -216,24 +216,14 @@ static inline void page_pool_recycle_direct(struct page_pool *pool, > >>>> page_pool_put_full_page(pool, page, true); > >>>> } > >>>> > >>>> -#define PAGE_POOL_DMA_USE_PP_FRAG_COUNT \ > >>>> - (sizeof(dma_addr_t) > sizeof(unsigned long)) > >>>> - > >>>> static inline dma_addr_t page_pool_get_dma_addr(struct page *page) > >>>> { > >>>> - dma_addr_t ret = page->dma_addr; > >>>> - > >>>> - if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT) > >>>> - ret |= (dma_addr_t)page->dma_addr_upper << 16 << 16; > >>>> - > >>>> - return ret; > >>>> + return page->dma_addr; > >>>> } > >>>> > >>>> static inline void page_pool_set_dma_addr(struct page *page, dma_addr_t addr) > >>>> { > >>>> page->dma_addr = addr; > >>>> - if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT) > >>>> - page->dma_addr_upper = upper_32_bits(addr); > >>>> } > >>>> > >>>> static inline void page_pool_set_frag_count(struct page *page, long nr) > >>>> diff --git a/net/core/page_pool.c b/net/core/page_pool.c > >>>> index 1a6978427d6c..9b60e4301a44 100644 > >>>> --- a/net/core/page_pool.c > >>>> +++ b/net/core/page_pool.c > >>>> @@ -49,6 +49,12 @@ static int page_pool_init(struct page_pool *pool, > >>>> * which is the XDP_TX use-case. > >>>> */ > >>>> if (pool->p.flags & PP_FLAG_DMA_MAP) { > >>>> + /* DMA-mapping is not supported on 32-bit systems with > >>>> + * 64-bit DMA mapping. > >>>> + */ > >>>> + if (sizeof(dma_addr_t) > sizeof(unsigned long)) > >>>> + return -EOPNOTSUPP; > >>>> + > >>>> if ((pool->p.dma_dir != DMA_FROM_DEVICE) && > >>>> (pool->p.dma_dir != DMA_BIDIRECTIONAL)) > >>>> return -EINVAL; > >>>> @@ -69,10 +75,6 @@ static int page_pool_init(struct page_pool *pool, > >>>> */ > >>>> } > >>>> > >>>> - if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT && > >>>> - pool->p.flags & PP_FLAG_PAGE_FRAG) > >>>> - return -EINVAL; > >>>> - > >>>> if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0) > >>>> return -ENOMEM; > >>>> > >>>> > >>> > >>> > >>> > >>> Git bisection log: > >>> > >>> ------------------------------------------------------------------------------- > >>> git bisect start > >>> # good: [bfc484fe6abba4b89ec9330e0e68778e2a9856b2] Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 > >>> git bisect good bfc484fe6abba4b89ec9330e0e68778e2a9856b2 > >>> # bad: [e851dfae4371d3c751f1e18e8eb5eba993de1467] Merge tag 'kgdb-5.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux > >>> git bisect bad e851dfae4371d3c751f1e18e8eb5eba993de1467 > >>> # bad: [dcd68326d29b62f3039e4f4d23d3e38f24d37360] Merge tag 'devicetree-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux > >>> git bisect bad dcd68326d29b62f3039e4f4d23d3e38f24d37360 > >>> # bad: [b7b98f868987cd3e86c9bd9a6db048614933d7a0] Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next > >>> git bisect bad b7b98f868987cd3e86c9bd9a6db048614933d7a0 > >>> # bad: [9fd3d5dced976640f588e0a866b9611db2d2cb37] net: ethernet: ave: Add compatible string and SoC-dependent data for NX1 SoC > >>> git bisect bad 9fd3d5dced976640f588e0a866b9611db2d2cb37 > >>> # good: [a96d317fb1a30b9f323548eb2ff05d4e4600ead9] ethernet: use eth_hw_addr_set() > >>> git bisect good a96d317fb1a30b9f323548eb2ff05d4e4600ead9 > >>> # good: [f5396b8a663f7a78ee5b75a47ee524b40795b265] ice: switchdev slow path > >>> git bisect good f5396b8a663f7a78ee5b75a47ee524b40795b265 > >>> # good: [20c3d9e45ba630a7156d682a40988c0e96be1b92] hamradio: use dev_addr_set() for setting device address > >>> git bisect good 20c3d9e45ba630a7156d682a40988c0e96be1b92 > >>> # bad: [a64b442137669c9e839c6a70965989b01b1253b7] net: dpaa2: add support for manual setup of IRQ coalesing > >>> git bisect bad a64b442137669c9e839c6a70965989b01b1253b7 > >>> # good: [30fc7efa38f21afa48b0be6bf2053e4c10ae2c78] net, neigh: Reject creating NUD_PERMANENT with NTF_MANAGED entries > >>> git bisect good 30fc7efa38f21afa48b0be6bf2053e4c10ae2c78 > >>> # bad: [13ad5ccc093ff448b99ac7e138e91e78796adb48] dt-bindings: net: dsa: qca8k: Document qca,sgmii-enable-pll > >>> git bisect bad 13ad5ccc093ff448b99ac7e138e91e78796adb48 > >>> # good: [40088915f547b52635f022c1e1e18df65ae3153a] Merge branch 'octeontx2-af-miscellaneous-changes-for-cpt' > >>> git bisect good 40088915f547b52635f022c1e1e18df65ae3153a > >>> # bad: [fdbf35df9c091db9c46e57e9938e3f7a4f603a7c] dt-bindings: net: dsa: qca8k: Add SGMII clock phase properties > >>> git bisect bad fdbf35df9c091db9c46e57e9938e3f7a4f603a7c > >>> # bad: [bacc8daf97d4199316328a5d18eeafbe447143c5] xen-netback: Remove redundant initialization of variable err > >>> git bisect bad bacc8daf97d4199316328a5d18eeafbe447143c5 > >>> # bad: [d00e60ee54b12de945b8493cf18c1ada9e422514] page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA > >>> git bisect bad d00e60ee54b12de945b8493cf18c1ada9e422514 > >>> # first bad commit: [d00e60ee54b12de945b8493cf18c1ada9e422514] page_pool: disable dma mapping support for 32-bit arch with 64-bit DMA > >>> ------------------------------------------------------------------------------- > >>> . > >>> > > > > . > >