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[PATCH] iommu/arm-smmu: Mark expected switch fall-through
by Yang Yingliang 16 Apr '20

16 Apr '20

From: Anders Roxell <anders.roxell(a)linaro.org> mainline inclusion from mainline-v5.3-rc5 commit 11f4fe9ba3c85a4efac7ec25e75056a9b612d9da category: bugfix bugzilla: 20500 CVE: NA ------------------------------------------------------------------------- Now that -Wimplicit-fallthrough is passed to GCC by default, the following warning shows up: ../drivers/iommu/arm-smmu-v3.c: In function ‘arm_smmu_write_strtab_ent’: ../drivers/iommu/arm-smmu-v3.c:1189:7: warning: this statement may fall through [-Wimplicit-fallthrough=] if (disable_bypass) ^ ../drivers/iommu/arm-smmu-v3.c:1191:3: note: here default: ^~~~~~~ Rework so that the compiler doesn't warn about fall-through. Make it clearer by calling 'BUG_ON()' when disable_bypass is set, and always 'break;' Signed-off-by: Anders Roxell <anders.roxell(a)linaro.org> Acked-by: Will Deacon <will(a)kernel.org> Signed-off-by: Joerg Roedel <jroedel(a)suse.de> Signed-off-by: Zhen Lei <thunder.leizhen(a)huawei.com> Reviewed-by: Hanjun Guo <guohanjun(a)huawei.com> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- drivers/iommu/arm-smmu-v3.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index e8f7bd3..5ee08ab 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -1226,8 +1226,8 @@ static void arm_smmu_write_strtab_ent(struct arm_smmu_device *smmu, u32 sid, ste_live = true; break; case STRTAB_STE_0_CFG_ABORT: - if (disable_bypass) - break; + BUG_ON(!disable_bypass); + break; default: BUG(); /* STE corruption */ } -- 1.8.3

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[PATCH] efi/memreserve: Register reservations as 'reserved' in /proc/iomem
by Yang Yingliang 16 Apr '20

16 Apr '20

From: Ard Biesheuvel <ardb(a)kernel.org> mainline inclusion from mainline-5.5-rc3 commit ab0eb16205b4 category: bugfix bugzilla: 27656 CVE: NA ------------------------------------------------- Memory regions that are reserved using efi_mem_reserve_persistent() are recorded in a special EFI config table which survives kexec, allowing the incoming kernel to honour them as well. However, such reservations are not visible in /proc/iomem, and so the kexec tools that load the incoming kernel and its initrd into memory may overwrite these reserved regions before the incoming kernel has a chance to reserve them from further use. Address this problem by adding these reservations to /proc/iomem as they are created. Note that reservations that are inherited from a previous kernel are memblock_reserve()'d early on, so they are already visible in /proc/iomem. Tested-by: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com> Tested-by: Bhupesh Sharma <bhsharma(a)redhat.com> Signed-off-by: Ard Biesheuvel <ardb(a)kernel.org> Reviewed-by: Bhupesh Sharma <bhsharma(a)redhat.com> Cc: <stable(a)vger.kernel.org> # v5.4+ Cc: Andy Shevchenko <andriy.shevchenko(a)linux.intel.com> Cc: Arvind Sankar <nivedita(a)alum.mit.edu> Cc: linux-efi(a)vger.kernel.org Link: https://lkml.kernel.org/r/20191206165542.31469-2-ardb@kernel.org Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> Reviewed-by: Hanjun Guo <guohanjun(a)huawei.com> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- drivers/firmware/efi/efi.c | 28 ++++++++++++++++++++++++++-- 1 file changed, 26 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index e304439..f386a78 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -998,6 +998,24 @@ static int __init efi_memreserve_map_root(void) return 0; } +static int efi_mem_reserve_iomem(phys_addr_t addr, u64 size) +{ + struct resource *res, *parent; + + res = kzalloc(sizeof(struct resource), GFP_ATOMIC); + if (!res) + return -ENOMEM; + + res->name = "reserved"; + res->flags = IORESOURCE_MEM; + res->start = addr; + res->end = addr + size - 1; + + /* we expect a conflict with a 'System RAM' region */ + parent = request_resource_conflict(&iomem_resource, res); + return parent ? request_resource(parent, res) : 0; +} + int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) { struct linux_efi_memreserve *rsv; @@ -1022,7 +1040,7 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) rsv->entry[index].size = size; memunmap(rsv); - return 0; + return efi_mem_reserve_iomem(addr, size); } memunmap(rsv); } @@ -1032,6 +1050,12 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) if (!rsv) return -ENOMEM; + rc = efi_mem_reserve_iomem(__pa(rsv), SZ_4K); + if (rc) { + free_page((unsigned long)rsv); + return rc; + } + /* * The memremap() call above assumes that a linux_efi_memreserve entry * never crosses a page boundary, so let's ensure that this remains true @@ -1048,7 +1072,7 @@ int __ref efi_mem_reserve_persistent(phys_addr_t addr, u64 size) efi_memreserve_root->next = __pa(rsv); spin_unlock(&efi_mem_reserve_persistent_lock); - return 0; + return efi_mem_reserve_iomem(addr, size); } static int __init efi_memreserve_root_init(void) -- 1.8.3

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[PATCH] compat_ioctl: handle SIOCOUTQNSD
by Yang Yingliang 16 Apr '20

16 Apr '20

From: Arnd Bergmann <arnd(a)arndb.de> mainline inclusion from mainline-v5.5-rc1 commit 9d7bf41fafa5b5ddd4c13eb39446b0045f0a8167 category: bugfix bugzilla: 26804 CVE: NA ------------------------------------- Unlike the normal SIOCOUTQ, SIOCOUTQNSD was never handled in compat mode. Add it to the common socket compat handler along with similar ones. Fixes: 2f4e1b397097 ("tcp: ioctl type SIOCOUTQNSD returns amount of data not sent") Cc: Eric Dumazet <edumazet(a)google.com> Cc: netdev(a)vger.kernel.org Cc: "David S. Miller" <davem(a)davemloft.net> Signed-off-by: Arnd Bergmann <arnd(a)arndb.de> Signed-off-by: guodeqing <geffrey.guo(a)huawei.com> Reviewed-by: Wenan Mao <maowenan(a)huawei.com> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- net/socket.c | 1 + 1 file changed, 1 insertion(+) diff --git a/net/socket.c b/net/socket.c index 1290aad..1030a61 100644 --- a/net/socket.c +++ b/net/socket.c @@ -3240,6 +3240,7 @@ static int compat_sock_ioctl_trans(struct file *file, struct socket *sock, case SIOCSARP: case SIOCGARP: case SIOCDARP: + case SIOCOUTQNSD: case SIOCATMARK: return sock_do_ioctl(net, sock, cmd, arg); } -- 1.8.3

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[PATCH 01/43] chardev: Avoid potential use-after-free in 'chrdev_open()'
by Yang Yingliang 16 Apr '20

16 Apr '20

From: Will Deacon <will(a)kernel.org> commit 68faa679b8be1a74e6663c21c3a9d25d32f1c079 upstream. 'chrdev_open()' calls 'cdev_get()' to obtain a reference to the 'struct cdev *' stashed in the 'i_cdev' field of the target inode structure. If the pointer is NULL, then it is initialised lazily by looking up the kobject in the 'cdev_map' and so the whole procedure is protected by the 'cdev_lock' spinlock to serialise initialisation of the shared pointer. Unfortunately, it is possible for the initialising thread to fail *after* installing the new pointer, for example if the subsequent '->open()' call on the file fails. In this case, 'cdev_put()' is called, the reference count on the kobject is dropped and, if nobody else has taken a reference, the release function is called which finally clears 'inode->i_cdev' from 'cdev_purge()' before potentially freeing the object. The problem here is that a racing thread can happily take the 'cdev_lock' and see the non-NULL pointer in the inode, which can result in a refcount increment from zero and a warning: | ------------[ cut here ]------------ | refcount_t: addition on 0; use-after-free. | WARNING: CPU: 2 PID: 6385 at lib/refcount.c:25 refcount_warn_saturate+0x6d/0xf0 | Modules linked in: | CPU: 2 PID: 6385 Comm: repro Not tainted 5.5.0-rc2+ #22 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 | RIP: 0010:refcount_warn_saturate+0x6d/0xf0 | Code: 05 55 9a 15 01 01 e8 9d aa c8 ff 0f 0b c3 80 3d 45 9a 15 01 00 75 ce 48 c7 c7 00 9c 62 b3 c6 08 | RSP: 0018:ffffb524c1b9bc70 EFLAGS: 00010282 | RAX: 0000000000000000 RBX: ffff9e9da1f71390 RCX: 0000000000000000 | RDX: ffff9e9dbbd27618 RSI: ffff9e9dbbd18798 RDI: ffff9e9dbbd18798 | RBP: 0000000000000000 R08: 000000000000095f R09: 0000000000000039 | R10: 0000000000000000 R11: ffffb524c1b9bb20 R12: ffff9e9da1e8c700 | R13: ffffffffb25ee8b0 R14: 0000000000000000 R15: ffff9e9da1e8c700 | FS: 00007f3b87d26700(0000) GS:ffff9e9dbbd00000(0000) knlGS:0000000000000000 | CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 | CR2: 00007fc16909c000 CR3: 000000012df9c000 CR4: 00000000000006e0 | DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 | DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 | Call Trace: | kobject_get+0x5c/0x60 | cdev_get+0x2b/0x60 | chrdev_open+0x55/0x220 | ? cdev_put.part.3+0x20/0x20 | do_dentry_open+0x13a/0x390 | path_openat+0x2c8/0x1470 | do_filp_open+0x93/0x100 | ? selinux_file_ioctl+0x17f/0x220 | do_sys_open+0x186/0x220 | do_syscall_64+0x48/0x150 | entry_SYSCALL_64_after_hwframe+0x44/0xa9 | RIP: 0033:0x7f3b87efcd0e | Code: 89 54 24 08 e8 a3 f4 ff ff 8b 74 24 0c 48 8b 3c 24 41 89 c0 44 8b 54 24 08 b8 01 01 00 00 89 f4 | RSP: 002b:00007f3b87d259f0 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 | RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f3b87efcd0e | RDX: 0000000000000000 RSI: 00007f3b87d25a80 RDI: 00000000ffffff9c | RBP: 00007f3b87d25e90 R08: 0000000000000000 R09: 0000000000000000 | R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe188f504e | R13: 00007ffe188f504f R14: 00007f3b87d26700 R15: 0000000000000000 | ---[ end trace 24f53ca58db8180a ]--- Since 'cdev_get()' can already fail to obtain a reference, simply move it over to use 'kobject_get_unless_zero()' instead of 'kobject_get()', which will cause the racing thread to return -ENXIO if the initialising thread fails unexpectedly. Cc: Hillf Danton <hdanton(a)sina.com> Cc: Andrew Morton <akpm(a)linux-foundation.org> Cc: Al Viro <viro(a)zeniv.linux.org.uk> Reported-by: syzbot+82defefbbd8527e1c2cb(a)syzkaller.appspotmail.com Signed-off-by: Will Deacon <will(a)kernel.org> Cc: stable <stable(a)vger.kernel.org> Link: https://lore.kernel.org/r/20191219120203.32691-1-will@kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- fs/char_dev.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/char_dev.c b/fs/char_dev.c index 8a63cfa..5fffd50 100644 --- a/fs/char_dev.c +++ b/fs/char_dev.c @@ -361,7 +361,7 @@ static struct kobject *cdev_get(struct cdev *p) if (owner && !try_module_get(owner)) return NULL; - kobj = kobject_get(&p->kobj); + kobj = kobject_get_unless_zero(&p->kobj); if (!kobj) module_put(owner); return kobj; -- 1.8.3

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[PATCH] net: hns3: modify the Makefile
by Yang Yingliang 15 Apr '20

15 Apr '20

From: youshengzui <youshengzui(a)huawei.com> driver inclusion category: feature bugzilla: NA CVE: NA ------------------------------ This patch is used to modify the Makefile Signed-off-by: youshengzui <youshengzui(a)huawei.com> Reviewed-by: Weiwei Deng <dengweiwei(a)huawei.com> Reviewed-by: Junxin Chen <chenjunxin1(a)huawei.com> Reviewed-by: Yongxin Li <liyongxin1(a)huawei.com> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- drivers/net/ethernet/hisilicon/hns3/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/hisilicon/hns3/Makefile b/drivers/net/ethernet/hisilicon/hns3/Makefile index 6653e81..f53983e 100644 --- a/drivers/net/ethernet/hisilicon/hns3/Makefile +++ b/drivers/net/ethernet/hisilicon/hns3/Makefile @@ -28,7 +28,7 @@ ccflags-y += -I$(PWD) \ obj-$(CONFIG_HNS3) += hnae3.o #### compile hns3.ko -HNS3_OBJS = hns3_enet.o \ +HNS3_OBJS = hns3_enet.o \ hns3_ethtool.o \ hns3_debugfs.o HNS3_OBJS_IT = hns-customer/hns3_enet_it.o \ -- 1.8.3

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[PATCH 0/6] Support MPAM ACPI
by Wang ShaoBo 14 Apr '20

14 Apr '20

hulk inclusion category: feature bugzilla: 28055 CVE: NA ------------------------------ MPAM driver temporarily force initializing cache/memory unwillingly, Futher We should make it compatible with P2, P4, P6 machine in the future, it's eager to introduce new method to get MSCs' info from BIOS/DT. Note arm hasn't reached a final conclusion about MPAM ACPI Description, BIOS implemented one temporary version according to v1 spec. MPAM ACPI Table organized as follow: *******Address increased by raw******** [DIE0] Memory node: mc[proximity:0] [DIE1] Memory node: mc[proximity:1] [DIE0] Memory node: mc[proximity:0] [DIE2] Memory node: mc[proximity:2] [DIE3] Memory node: mc[proximity:3] [DIE0] Cache node: cache[PPTT_ref:$a] [PARTITION0] Cache node: cache[PPTT_ref:$a] [PARTITION1] Cache node: cache[PPTT_ref:$a] [PARTITION2] Cache node: cache[PPTT_ref:$a] [PARTITION3] Cache node: cache[PPTT_ref:$a] [PARTITION4] Cache node: cache[PPTT_ref:$a] [PARTITION5] Cache node: cache[PPTT_ref:$a] [PARTITION6] Cache node: cache[PPTT_ref:$a] [PARTITION7] Cache node: cache[PPTT_ref:$a] [DIE1] Cache node: cache[PPTT_ref:$b] [PARTITION0] Cache node: cache[PPTT_ref:$b] [PARTITION1] Cache node: cache[PPTT_ref:$b] ... We use PPTT_ref to decide which DIE the cache node belongs to, and use proximity to decide memory node. it is tricky, but still usefull. James Morse (3): ACPI / processor: Add helper to convert acpi_id to a phys_cpuid ACPI / PPTT: Add helper to validate cache nodes from an offset [dead] ACPI / PPTT: Filthy hack to find _a_ backwards reference in the PPTT [ROTTEN] Wang ShaoBo (3): ACPI / PPTT: cacheinfo: Label caches based on fw_token ACPI 6.x: Add definitions for MPAM table MPAM / ACPI: Refactoring MPAM init process and set MPAM ACPI as entrance arch/arm64/Kconfig | 2 + arch/arm64/include/asm/acpi.h | 4 + arch/arm64/include/asm/mpam_resource.h | 15 +- arch/arm64/include/asm/mpam_sched.h | 8 +- arch/arm64/kernel/mpam.c | 246 ++++++++++++++++++------ drivers/acpi/arm64/Kconfig | 3 + drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/mpam.c | 249 +++++++++++++++++++++++++ drivers/acpi/pptt.c | 143 ++++++++++++++ drivers/acpi/processor_core.c | 16 ++ include/acpi/actbl2.h | 58 ++++++ include/acpi/processor.h | 1 + include/linux/acpi.h | 8 + 13 files changed, 698 insertions(+), 56 deletions(-) create mode 100644 drivers/acpi/arm64/mpam.c -- 2.20.1

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[PATCH 1/5] mm/vmalloc.c: keep track of free blocks for vmap allocation
by Yang Yingliang 14 Apr '20

14 Apr '20

From: "Uladzislau Rezki (Sony)" <urezki(a)gmail.com> mainline inclusion from mainline-5.2-rc1 commit 68ad4a3304335358f95a417f2a2b0c909e5119c4 category: bugfix bugzilla: 15766 CVE: NA ------------------------------------------------- Patch series "improve vmap allocation", v3. Objective --------- Please have a look for the description at: https://lkml.org/lkml/2018/10/19/786 but let me also summarize it a bit here as well. The current implementation has O(N) complexity. Requests with different permissive parameters can lead to long allocation time. When i say "long" i mean milliseconds. Description ----------- This approach organizes the KVA memory layout into free areas of the 1-ULONG_MAX range, i.e. an allocation is done over free areas lookups, instead of finding a hole between two busy blocks. It allows to have lower number of objects which represent the free space, therefore to have less fragmented memory allocator. Because free blocks are always as large as possible. It uses the augment tree where all free areas are sorted in ascending order of va->va_start address in pair with linked list that provides O(1) access to prev/next elements. Since the tree is augment, we also maintain the "subtree_max_size" of VA that reflects a maximum available free block in its left or right sub-tree. Knowing that, we can easily traversal toward the lowest (left most path) free area. Allocation: ~O(log(N)) complexity. It is sequential allocation method therefore tends to maximize locality. The search is done until a first suitable block is large enough to encompass the requested parameters. Bigger areas are split. I copy paste here the description of how the area is split, since i described it in https://lkml.org/lkml/2018/10/19/786 <snip> A free block can be split by three different ways. Their names are FL_FIT_TYPE, LE_FIT_TYPE/RE_FIT_TYPE and NE_FIT_TYPE, i.e. they correspond to how requested size and alignment fit to a free block. FL_FIT_TYPE - in this case a free block is just removed from the free list/tree because it fully fits. Comparing with current design there is an extra work with rb-tree updating. LE_FIT_TYPE/RE_FIT_TYPE - left/right edges fit. In this case what we do is just cutting a free block. It is as fast as a current design. Most of the vmalloc allocations just end up with this case, because the edge is always aligned to 1. NE_FIT_TYPE - Is much less common case. Basically it happens when requested size and alignment does not fit left nor right edges, i.e. it is between them. In this case during splitting we have to build a remaining left free area and place it back to the free list/tree. Comparing with current design there are two extra steps. First one is we have to allocate a new vmap_area structure. Second one we have to insert that remaining free block to the address sorted list/tree. In order to optimize a first case there is a cache with free_vmap objects. Instead of allocating from slab we just take an object from the cache and reuse it. Second one is pretty optimized. Since we know a start point in the tree we do not do a search from the top. Instead a traversal begins from a rb-tree node we split. <snip> De-allocation. ~O(log(N)) complexity. An area is not inserted straight away to the tree/list, instead we identify the spot first, checking if it can be merged around neighbors. The list provides O(1) access to prev/next, so it is pretty fast to check it. Summarizing. If merged then large coalesced areas are created, if not the area is just linked making more fragments. There is one more thing that i should mention here. After modification of VA node, its subtree_max_size is updated if it was/is the biggest area in its left or right sub-tree. Apart of that it can also be populated back to upper levels to fix the tree. For more details please have a look at the __augment_tree_propagate_from() function and the description. Tests and stressing ------------------- I use the "test_vmalloc.sh" test driver available under "tools/testing/selftests/vm/" since 5.1-rc1 kernel. Just trigger "sudo ./test_vmalloc.sh" to find out how to deal with it. Tested on different platforms including x86_64/i686/ARM64/x86_64_NUMA. Regarding last one, i do not have any physical access to NUMA system, therefore i emulated it. The time of stressing is days. If you run the test driver in "stress mode", you also need the patch that is in Andrew's tree but not in Linux 5.1-rc1. So, please apply it: http://git.cmpxchg.org/cgit.cgi/linux-mmotm.git/commit/?id=e0cf7749bade6da3… After massive testing, i have not identified any problems like memory leaks, crashes or kernel panics. I find it stable, but more testing would be good. Performance analysis -------------------- I have used two systems to test. One is i5-3320M CPU @ 2.60GHz and another is HiKey960(arm64) board. i5-3320M runs on 4.20 kernel, whereas Hikey960 uses 4.15 kernel. I have both system which could run on 5.1-rc1 as well, but the results have not been ready by time i an writing this. Currently it consist of 8 tests. There are three of them which correspond to different types of splitting(to compare with default). We have 3 ones(see above). Another 5 do allocations in different conditions. a) sudo ./test_vmalloc.sh performance When the test driver is run in "performance" mode, it runs all available tests pinned to first online CPU with sequential execution test order. We do it in order to get stable and repeatable results. Take a look at time difference in "long_busy_list_alloc_test". It is not surprising because the worst case is O(N). # i5-3320M How many cycles all tests took: CPU0=646919905370(default) cycles vs CPU0=193290498550(patched) cycles # See detailed table with results here: ftp://vps418301.ovh.net/incoming/vmap_test_results_v2/i5-3320M_performance_… ftp://vps418301.ovh.net/incoming/vmap_test_results_v2/i5-3320M_performance_… # Hikey960 8x CPUs How many cycles all tests took: CPU0=3478683207 cycles vs CPU0=463767978 cycles # See detailed table with results here: ftp://vps418301.ovh.net/incoming/vmap_test_results_v2/HiKey960_performance_… ftp://vps418301.ovh.net/incoming/vmap_test_results_v2/HiKey960_performance_… b) time sudo ./test_vmalloc.sh test_repeat_count=1 With this configuration, all tests are run on all available online CPUs. Before running each CPU shuffles its tests execution order. It gives random allocation behaviour. So it is rough comparison, but it puts in the picture for sure. # i5-3320M <default> vs <patched> real 101m22.813s real 0m56.805s user 0m0.011s user 0m0.015s sys 0m5.076s sys 0m0.023s # See detailed table with results here: ftp://vps418301.ovh.net/incoming/vmap_test_results_v2/i5-3320M_test_repeat_… ftp://vps418301.ovh.net/incoming/vmap_test_results_v2/i5-3320M_test_repeat_… # Hikey960 8x CPUs <default> vs <patched> real unknown real 4m25.214s user unknown user 0m0.011s sys unknown sys 0m0.670s I did not manage to complete this test on "default Hikey960" kernel version. After 24 hours it was still running, therefore i had to cancel it. That is why real/user/sys are "unknown". This patch (of 3): Currently an allocation of the new vmap area is done over busy list iteration(complexity O(n)) until a suitable hole is found between two busy areas. Therefore each new allocation causes the list being grown. Due to over fragmented list and different permissive parameters an allocation can take a long time. For example on embedded devices it is milliseconds. This patch organizes the KVA memory layout into free areas of the 1-ULONG_MAX range. It uses an augment red-black tree that keeps blocks sorted by their offsets in pair with linked list keeping the free space in order of increasing addresses. Nodes are augmented with the size of the maximum available free block in its left or right sub-tree. Thus, that allows to take a decision and traversal toward the block that will fit and will have the lowest start address, i.e. it is sequential allocation. Allocation: to allocate a new block a search is done over the tree until a suitable lowest(left most) block is large enough to encompass: the requested size, alignment and vstart point. If the block is bigger than requested size - it is split. De-allocation: when a busy vmap area is freed it can either be merged or inserted to the tree. Red-black tree allows efficiently find a spot whereas a linked list provides a constant-time access to previous and next blocks to check if merging can be done. In case of merging of de-allocated memory chunk a large coalesced area is created. Complexity: ~O(log(N)) [urezki(a)gmail.com: v3] Link: http://lkml.kernel.org/r/20190402162531.10888-2-urezki@gmail.com [urezki(a)gmail.com: v4] Link: http://lkml.kernel.org/r/20190406183508.25273-2-urezki@gmail.com Link: http://lkml.kernel.org/r/20190321190327.11813-2-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) <urezki(a)gmail.com> Reviewed-by: Roman Gushchin <guro(a)fb.com> Cc: Michal Hocko <mhocko(a)suse.com> Cc: Matthew Wilcox <willy(a)infradead.org> Cc: Thomas Garnier <thgarnie(a)google.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko(a)sonymobile.com> Cc: Steven Rostedt <rostedt(a)goodmis.org> Cc: Joel Fernandes <joelaf(a)google.com> Cc: Thomas Gleixner <tglx(a)linutronix.de> Cc: Ingo Molnar <mingo(a)elte.hu> Cc: Tejun Heo <tj(a)kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org> (cherry picked from commit 68ad4a3304335358f95a417f2a2b0c909e5119c4) Signed-off-by: Kefeng Wang <wangkefeng.wang(a)huawei.com> Reviewed-by: Hanjun Guo <guohanjun(a)huawei.com> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- include/linux/vmalloc.h | 6 +- mm/vmalloc.c | 1004 +++++++++++++++++++++++++++++++++++------------ 2 files changed, 763 insertions(+), 247 deletions(-) diff --git a/include/linux/vmalloc.h b/include/linux/vmalloc.h index 398e9c9..ad483378 100644 --- a/include/linux/vmalloc.h +++ b/include/linux/vmalloc.h @@ -45,12 +45,16 @@ struct vm_struct { struct vmap_area { unsigned long va_start; unsigned long va_end; + + /* + * Largest available free size in subtree. + */ + unsigned long subtree_max_size; unsigned long flags; struct rb_node rb_node; /* address sorted rbtree */ struct list_head list; /* address sorted list */ struct llist_node purge_list; /* "lazy purge" list */ struct vm_struct *vm; - struct rcu_head rcu_head; }; /* diff --git a/mm/vmalloc.c b/mm/vmalloc.c index f49ff8a..8b134c0 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -31,6 +31,7 @@ #include <linux/compiler.h> #include <linux/llist.h> #include <linux/bitops.h> +#include <linux/rbtree_augmented.h> #include <linux/uaccess.h> #include <asm/tlbflush.h> @@ -331,14 +332,67 @@ unsigned long vmalloc_to_pfn(const void *vmalloc_addr) LIST_HEAD(vmap_area_list); static LLIST_HEAD(vmap_purge_list); static struct rb_root vmap_area_root = RB_ROOT; +static bool vmap_initialized __read_mostly; -/* The vmap cache globals are protected by vmap_area_lock */ -static struct rb_node *free_vmap_cache; -static unsigned long cached_hole_size; -static unsigned long cached_vstart; -static unsigned long cached_align; +/* + * This kmem_cache is used for vmap_area objects. Instead of + * allocating from slab we reuse an object from this cache to + * make things faster. Especially in "no edge" splitting of + * free block. + */ +static struct kmem_cache *vmap_area_cachep; + +/* + * This linked list is used in pair with free_vmap_area_root. + * It gives O(1) access to prev/next to perform fast coalescing. + */ +static LIST_HEAD(free_vmap_area_list); + +/* + * This augment red-black tree represents the free vmap space. + * All vmap_area objects in this tree are sorted by va->va_start + * address. It is used for allocation and merging when a vmap + * object is released. + * + * Each vmap_area node contains a maximum available free block + * of its sub-tree, right or left. Therefore it is possible to + * find a lowest match of free area. + */ +static struct rb_root free_vmap_area_root = RB_ROOT; + +static __always_inline unsigned long +va_size(struct vmap_area *va) +{ + return (va->va_end - va->va_start); +} + +static __always_inline unsigned long +get_subtree_max_size(struct rb_node *node) +{ + struct vmap_area *va; + + va = rb_entry_safe(node, struct vmap_area, rb_node); + return va ? va->subtree_max_size : 0; +} -static unsigned long vmap_area_pcpu_hole; +/* + * Gets called when remove the node and rotate. + */ +static __always_inline unsigned long +compute_subtree_max_size(struct vmap_area *va) +{ + return max3(va_size(va), + get_subtree_max_size(va->rb_node.rb_left), + get_subtree_max_size(va->rb_node.rb_right)); +} + +RB_DECLARE_CALLBACKS(static, free_vmap_area_rb_augment_cb, + struct vmap_area, rb_node, unsigned long, subtree_max_size, + compute_subtree_max_size) + +static void purge_vmap_area_lazy(void); +static BLOCKING_NOTIFIER_HEAD(vmap_notify_list); +static unsigned long lazy_max_pages(void); static struct vmap_area *__find_vmap_area(unsigned long addr) { @@ -359,41 +413,522 @@ static struct vmap_area *__find_vmap_area(unsigned long addr) return NULL; } -static void __insert_vmap_area(struct vmap_area *va) -{ - struct rb_node **p = &vmap_area_root.rb_node; - struct rb_node *parent = NULL; - struct rb_node *tmp; +/* + * This function returns back addresses of parent node + * and its left or right link for further processing. + */ +static __always_inline struct rb_node ** +find_va_links(struct vmap_area *va, + struct rb_root *root, struct rb_node *from, + struct rb_node **parent) +{ + struct vmap_area *tmp_va; + struct rb_node **link; + + if (root) { + link = &root->rb_node; + if (unlikely(!*link)) { + *parent = NULL; + return link; + } + } else { + link = &from; + } - while (*p) { - struct vmap_area *tmp_va; + /* + * Go to the bottom of the tree. When we hit the last point + * we end up with parent rb_node and correct direction, i name + * it link, where the new va->rb_node will be attached to. + */ + do { + tmp_va = rb_entry(*link, struct vmap_area, rb_node); - parent = *p; - tmp_va = rb_entry(parent, struct vmap_area, rb_node); - if (va->va_start < tmp_va->va_end) - p = &(*p)->rb_left; - else if (va->va_end > tmp_va->va_start) - p = &(*p)->rb_right; + /* + * During the traversal we also do some sanity check. + * Trigger the BUG() if there are sides(left/right) + * or full overlaps. + */ + if (va->va_start < tmp_va->va_end && + va->va_end <= tmp_va->va_start) + link = &(*link)->rb_left; + else if (va->va_end > tmp_va->va_start && + va->va_start >= tmp_va->va_end) + link = &(*link)->rb_right; else BUG(); + } while (*link); + + *parent = &tmp_va->rb_node; + return link; +} + +static __always_inline struct list_head * +get_va_next_sibling(struct rb_node *parent, struct rb_node **link) +{ + struct list_head *list; + + if (unlikely(!parent)) + /* + * The red-black tree where we try to find VA neighbors + * before merging or inserting is empty, i.e. it means + * there is no free vmap space. Normally it does not + * happen but we handle this case anyway. + */ + return NULL; + + list = &rb_entry(parent, struct vmap_area, rb_node)->list; + return (&parent->rb_right == link ? list->next : list); +} + +static __always_inline void +link_va(struct vmap_area *va, struct rb_root *root, + struct rb_node *parent, struct rb_node **link, struct list_head *head) +{ + /* + * VA is still not in the list, but we can + * identify its future previous list_head node. + */ + if (likely(parent)) { + head = &rb_entry(parent, struct vmap_area, rb_node)->list; + if (&parent->rb_right != link) + head = head->prev; } - rb_link_node(&va->rb_node, parent, p); - rb_insert_color(&va->rb_node, &vmap_area_root); + /* Insert to the rb-tree */ + rb_link_node(&va->rb_node, parent, link); + if (root == &free_vmap_area_root) { + /* + * Some explanation here. Just perform simple insertion + * to the tree. We do not set va->subtree_max_size to + * its current size before calling rb_insert_augmented(). + * It is because of we populate the tree from the bottom + * to parent levels when the node _is_ in the tree. + * + * Therefore we set subtree_max_size to zero after insertion, + * to let __augment_tree_propagate_from() puts everything to + * the correct order later on. + */ + rb_insert_augmented(&va->rb_node, + root, &free_vmap_area_rb_augment_cb); + va->subtree_max_size = 0; + } else { + rb_insert_color(&va->rb_node, root); + } - /* address-sort this list */ - tmp = rb_prev(&va->rb_node); - if (tmp) { - struct vmap_area *prev; - prev = rb_entry(tmp, struct vmap_area, rb_node); - list_add_rcu(&va->list, &prev->list); - } else - list_add_rcu(&va->list, &vmap_area_list); + /* Address-sort this list */ + list_add(&va->list, head); } -static void purge_vmap_area_lazy(void); +static __always_inline void +unlink_va(struct vmap_area *va, struct rb_root *root) +{ + /* + * During merging a VA node can be empty, therefore + * not linked with the tree nor list. Just check it. + */ + if (!RB_EMPTY_NODE(&va->rb_node)) { + if (root == &free_vmap_area_root) + rb_erase_augmented(&va->rb_node, + root, &free_vmap_area_rb_augment_cb); + else + rb_erase(&va->rb_node, root); -static BLOCKING_NOTIFIER_HEAD(vmap_notify_list); + list_del(&va->list); + RB_CLEAR_NODE(&va->rb_node); + } +} + +/* + * This function populates subtree_max_size from bottom to upper + * levels starting from VA point. The propagation must be done + * when VA size is modified by changing its va_start/va_end. Or + * in case of newly inserting of VA to the tree. + * + * It means that __augment_tree_propagate_from() must be called: + * - After VA has been inserted to the tree(free path); + * - After VA has been shrunk(allocation path); + * - After VA has been increased(merging path). + * + * Please note that, it does not mean that upper parent nodes + * and their subtree_max_size are recalculated all the time up + * to the root node. + * + * 4--8 + * /\ + * / \ + * / \ + * 2--2 8--8 + * + * For example if we modify the node 4, shrinking it to 2, then + * no any modification is required. If we shrink the node 2 to 1 + * its subtree_max_size is updated only, and set to 1. If we shrink + * the node 8 to 6, then its subtree_max_size is set to 6 and parent + * node becomes 4--6. + */ +static __always_inline void +augment_tree_propagate_from(struct vmap_area *va) +{ + struct rb_node *node = &va->rb_node; + unsigned long new_va_sub_max_size; + + while (node) { + va = rb_entry(node, struct vmap_area, rb_node); + new_va_sub_max_size = compute_subtree_max_size(va); + + /* + * If the newly calculated maximum available size of the + * subtree is equal to the current one, then it means that + * the tree is propagated correctly. So we have to stop at + * this point to save cycles. + */ + if (va->subtree_max_size == new_va_sub_max_size) + break; + + va->subtree_max_size = new_va_sub_max_size; + node = rb_parent(&va->rb_node); + } +} + +static void +insert_vmap_area(struct vmap_area *va, + struct rb_root *root, struct list_head *head) +{ + struct rb_node **link; + struct rb_node *parent; + + link = find_va_links(va, root, NULL, &parent); + link_va(va, root, parent, link, head); +} + +static void +insert_vmap_area_augment(struct vmap_area *va, + struct rb_node *from, struct rb_root *root, + struct list_head *head) +{ + struct rb_node **link; + struct rb_node *parent; + + if (from) + link = find_va_links(va, NULL, from, &parent); + else + link = find_va_links(va, root, NULL, &parent); + + link_va(va, root, parent, link, head); + augment_tree_propagate_from(va); +} + +/* + * Merge de-allocated chunk of VA memory with previous + * and next free blocks. If coalesce is not done a new + * free area is inserted. If VA has been merged, it is + * freed. + */ +static __always_inline void +merge_or_add_vmap_area(struct vmap_area *va, + struct rb_root *root, struct list_head *head) +{ + struct vmap_area *sibling; + struct list_head *next; + struct rb_node **link; + struct rb_node *parent; + bool merged = false; + + /* + * Find a place in the tree where VA potentially will be + * inserted, unless it is merged with its sibling/siblings. + */ + link = find_va_links(va, root, NULL, &parent); + + /* + * Get next node of VA to check if merging can be done. + */ + next = get_va_next_sibling(parent, link); + if (unlikely(next == NULL)) + goto insert; + + /* + * start end + * | | + * |<------VA------>|<-----Next----->| + * | | + * start end + */ + if (next != head) { + sibling = list_entry(next, struct vmap_area, list); + if (sibling->va_start == va->va_end) { + sibling->va_start = va->va_start; + + /* Check and update the tree if needed. */ + augment_tree_propagate_from(sibling); + + /* Remove this VA, it has been merged. */ + unlink_va(va, root); + + /* Free vmap_area object. */ + kmem_cache_free(vmap_area_cachep, va); + + /* Point to the new merged area. */ + va = sibling; + merged = true; + } + } + + /* + * start end + * | | + * |<-----Prev----->|<------VA------>| + * | | + * start end + */ + if (next->prev != head) { + sibling = list_entry(next->prev, struct vmap_area, list); + if (sibling->va_end == va->va_start) { + sibling->va_end = va->va_end; + + /* Check and update the tree if needed. */ + augment_tree_propagate_from(sibling); + + /* Remove this VA, it has been merged. */ + unlink_va(va, root); + + /* Free vmap_area object. */ + kmem_cache_free(vmap_area_cachep, va); + + return; + } + } + +insert: + if (!merged) { + link_va(va, root, parent, link, head); + augment_tree_propagate_from(va); + } +} + +static __always_inline bool +is_within_this_va(struct vmap_area *va, unsigned long size, + unsigned long align, unsigned long vstart) +{ + unsigned long nva_start_addr; + + if (va->va_start > vstart) + nva_start_addr = ALIGN(va->va_start, align); + else + nva_start_addr = ALIGN(vstart, align); + + /* Can be overflowed due to big size or alignment. */ + if (nva_start_addr + size < nva_start_addr || + nva_start_addr < vstart) + return false; + + return (nva_start_addr + size <= va->va_end); +} + +/* + * Find the first free block(lowest start address) in the tree, + * that will accomplish the request corresponding to passing + * parameters. + */ +static __always_inline struct vmap_area * +find_vmap_lowest_match(unsigned long size, + unsigned long align, unsigned long vstart) +{ + struct vmap_area *va; + struct rb_node *node; + unsigned long length; + + /* Start from the root. */ + node = free_vmap_area_root.rb_node; + + /* Adjust the search size for alignment overhead. */ + length = size + align - 1; + + while (node) { + va = rb_entry(node, struct vmap_area, rb_node); + + if (get_subtree_max_size(node->rb_left) >= length && + vstart < va->va_start) { + node = node->rb_left; + } else { + if (is_within_this_va(va, size, align, vstart)) + return va; + + /* + * Does not make sense to go deeper towards the right + * sub-tree if it does not have a free block that is + * equal or bigger to the requested search length. + */ + if (get_subtree_max_size(node->rb_right) >= length) { + node = node->rb_right; + continue; + } + + /* + * OK. We roll back and find the fist right sub-tree, + * that will satisfy the search criteria. It can happen + * only once due to "vstart" restriction. + */ + while ((node = rb_parent(node))) { + va = rb_entry(node, struct vmap_area, rb_node); + if (is_within_this_va(va, size, align, vstart)) + return va; + + if (get_subtree_max_size(node->rb_right) >= length && + vstart <= va->va_start) { + node = node->rb_right; + break; + } + } + } + } + + return NULL; +} + +enum fit_type { + NOTHING_FIT = 0, + FL_FIT_TYPE = 1, /* full fit */ + LE_FIT_TYPE = 2, /* left edge fit */ + RE_FIT_TYPE = 3, /* right edge fit */ + NE_FIT_TYPE = 4 /* no edge fit */ +}; + +static __always_inline enum fit_type +classify_va_fit_type(struct vmap_area *va, + unsigned long nva_start_addr, unsigned long size) +{ + enum fit_type type; + + /* Check if it is within VA. */ + if (nva_start_addr < va->va_start || + nva_start_addr + size > va->va_end) + return NOTHING_FIT; + + /* Now classify. */ + if (va->va_start == nva_start_addr) { + if (va->va_end == nva_start_addr + size) + type = FL_FIT_TYPE; + else + type = LE_FIT_TYPE; + } else if (va->va_end == nva_start_addr + size) { + type = RE_FIT_TYPE; + } else { + type = NE_FIT_TYPE; + } + + return type; +} + +static __always_inline int +adjust_va_to_fit_type(struct vmap_area *va, + unsigned long nva_start_addr, unsigned long size, + enum fit_type type) +{ + struct vmap_area *lva; + + if (type == FL_FIT_TYPE) { + /* + * No need to split VA, it fully fits. + * + * | | + * V NVA V + * |---------------| + */ + unlink_va(va, &free_vmap_area_root); + kmem_cache_free(vmap_area_cachep, va); + } else if (type == LE_FIT_TYPE) { + /* + * Split left edge of fit VA. + * + * | | + * V NVA V R + * |-------|-------| + */ + va->va_start += size; + } else if (type == RE_FIT_TYPE) { + /* + * Split right edge of fit VA. + * + * | | + * L V NVA V + * |-------|-------| + */ + va->va_end = nva_start_addr; + } else if (type == NE_FIT_TYPE) { + /* + * Split no edge of fit VA. + * + * | | + * L V NVA V R + * |---|-------|---| + */ + lva = kmem_cache_alloc(vmap_area_cachep, GFP_NOWAIT); + if (unlikely(!lva)) + return -1; + + /* + * Build the remainder. + */ + lva->va_start = va->va_start; + lva->va_end = nva_start_addr; + + /* + * Shrink this VA to remaining size. + */ + va->va_start = nva_start_addr + size; + } else { + return -1; + } + + if (type != FL_FIT_TYPE) { + augment_tree_propagate_from(va); + + if (type == NE_FIT_TYPE) + insert_vmap_area_augment(lva, &va->rb_node, + &free_vmap_area_root, &free_vmap_area_list); + } + + return 0; +} + +/* + * Returns a start address of the newly allocated area, if success. + * Otherwise a vend is returned that indicates failure. + */ +static __always_inline unsigned long +__alloc_vmap_area(unsigned long size, unsigned long align, + unsigned long vstart, unsigned long vend, int node) +{ + unsigned long nva_start_addr; + struct vmap_area *va; + enum fit_type type; + int ret; + + va = find_vmap_lowest_match(size, align, vstart); + if (unlikely(!va)) + return vend; + + if (va->va_start > vstart) + nva_start_addr = ALIGN(va->va_start, align); + else + nva_start_addr = ALIGN(vstart, align); + + /* Check the "vend" restriction. */ + if (nva_start_addr + size > vend) + return vend; + + /* Classify what we have found. */ + type = classify_va_fit_type(va, nva_start_addr, size); + if (WARN_ON_ONCE(type == NOTHING_FIT)) + return vend; + + /* Update the free vmap_area. */ + ret = adjust_va_to_fit_type(va, nva_start_addr, size, type); + if (ret) + return vend; + + return nva_start_addr; +} /* * Allocate a region of KVA of the specified size and alignment, within the @@ -405,18 +940,19 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, int node, gfp_t gfp_mask) { struct vmap_area *va; - struct rb_node *n; unsigned long addr; int purged = 0; - struct vmap_area *first; BUG_ON(!size); BUG_ON(offset_in_page(size)); BUG_ON(!is_power_of_2(align)); + if (unlikely(!vmap_initialized)) + return ERR_PTR(-EBUSY); + might_sleep(); - va = kmalloc_node(sizeof(struct vmap_area), + va = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask & GFP_RECLAIM_MASK, node); if (unlikely(!va)) return ERR_PTR(-ENOMEM); @@ -429,87 +965,20 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, retry: spin_lock(&vmap_area_lock); - /* - * Invalidate cache if we have more permissive parameters. - * cached_hole_size notes the largest hole noticed _below_ - * the vmap_area cached in free_vmap_cache: if size fits - * into that hole, we want to scan from vstart to reuse - * the hole instead of allocating above free_vmap_cache. - * Note that __free_vmap_area may update free_vmap_cache - * without updating cached_hole_size or cached_align. - */ - if (!free_vmap_cache || - size < cached_hole_size || - vstart < cached_vstart || - align < cached_align) { -nocache: - cached_hole_size = 0; - free_vmap_cache = NULL; - } - /* record if we encounter less permissive parameters */ - cached_vstart = vstart; - cached_align = align; - - /* find starting point for our search */ - if (free_vmap_cache) { - first = rb_entry(free_vmap_cache, struct vmap_area, rb_node); - addr = ALIGN(first->va_end, align); - if (addr < vstart) - goto nocache; - if (addr + size < addr) - goto overflow; - - } else { - addr = ALIGN(vstart, align); - if (addr + size < addr) - goto overflow; - - n = vmap_area_root.rb_node; - first = NULL; - - while (n) { - struct vmap_area *tmp; - tmp = rb_entry(n, struct vmap_area, rb_node); - if (tmp->va_end >= addr) { - first = tmp; - if (tmp->va_start <= addr) - break; - n = n->rb_left; - } else - n = n->rb_right; - } - - if (!first) - goto found; - } - /* from the starting point, walk areas until a suitable hole is found */ - while (addr + size > first->va_start && addr + size <= vend) { - if (addr + cached_hole_size < first->va_start) - cached_hole_size = first->va_start - addr; - addr = ALIGN(first->va_end, align); - if (addr + size < addr) - goto overflow; - - if (list_is_last(&first->list, &vmap_area_list)) - goto found; - - first = list_next_entry(first, list); - } - -found: /* - * Check also calculated address against the vstart, - * because it can be 0 because of big align request. + * If an allocation fails, the "vend" address is + * returned. Therefore trigger the overflow path. */ - if (addr + size > vend || addr < vstart) + addr = __alloc_vmap_area(size, align, vstart, vend, node); + if (unlikely(addr == vend)) goto overflow; va->va_start = addr; va->va_end = addr + size; va->flags = 0; - __insert_vmap_area(va); - free_vmap_cache = &va->rb_node; + insert_vmap_area(va, &vmap_area_root, &vmap_area_list); + spin_unlock(&vmap_area_lock); BUG_ON(!IS_ALIGNED(va->va_start, align)); @@ -538,7 +1007,8 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) pr_warn("vmap allocation for size %lu failed: use vmalloc=<size> to increase size\n", size); - kfree(va); + + kmem_cache_free(vmap_area_cachep, va); return ERR_PTR(-EBUSY); } @@ -558,35 +1028,16 @@ static void __free_vmap_area(struct vmap_area *va) { BUG_ON(RB_EMPTY_NODE(&va->rb_node)); - if (free_vmap_cache) { - if (va->va_end < cached_vstart) { - free_vmap_cache = NULL; - } else { - struct vmap_area *cache; - cache = rb_entry(free_vmap_cache, struct vmap_area, rb_node); - if (va->va_start <= cache->va_start) { - free_vmap_cache = rb_prev(&va->rb_node); - /* - * We don't try to update cached_hole_size or - * cached_align, but it won't go very wrong. - */ - } - } - } - rb_erase(&va->rb_node, &vmap_area_root); - RB_CLEAR_NODE(&va->rb_node); - list_del_rcu(&va->list); - /* - * Track the highest possible candidate for pcpu area - * allocation. Areas outside of vmalloc area can be returned - * here too, consider only end addresses which fall inside - * vmalloc area proper. + * Remove from the busy tree/list. */ - if (va->va_end > VMALLOC_START && va->va_end <= VMALLOC_END) - vmap_area_pcpu_hole = max(vmap_area_pcpu_hole, va->va_end); + unlink_va(va, &vmap_area_root); - kfree_rcu(va, rcu_head); + /* + * Merge VA with its neighbors, otherwise just add it. + */ + merge_or_add_vmap_area(va, + &free_vmap_area_root, &free_vmap_area_list); } /* @@ -787,8 +1238,6 @@ static struct vmap_area *find_vmap_area(unsigned long addr) #define VMAP_BLOCK_SIZE (VMAP_BBMAP_BITS * PAGE_SIZE) -static bool vmap_initialized __read_mostly = false; - struct vmap_block_queue { spinlock_t lock; struct list_head free; @@ -1242,12 +1691,58 @@ void __init vm_area_register_early(struct vm_struct *vm, size_t align) vm_area_add_early(vm); } +static void vmap_init_free_space(void) +{ + unsigned long vmap_start = 1; + const unsigned long vmap_end = ULONG_MAX; + struct vmap_area *busy, *free; + + /* + * B F B B B F + * -|-----|.....|-----|-----|-----|.....|- + * | The KVA space | + * |<--------------------------------->| + */ + list_for_each_entry(busy, &vmap_area_list, list) { + if (busy->va_start - vmap_start > 0) { + free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT); + if (!WARN_ON_ONCE(!free)) { + free->va_start = vmap_start; + free->va_end = busy->va_start; + + insert_vmap_area_augment(free, NULL, + &free_vmap_area_root, + &free_vmap_area_list); + } + } + + vmap_start = busy->va_end; + } + + if (vmap_end - vmap_start > 0) { + free = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT); + if (!WARN_ON_ONCE(!free)) { + free->va_start = vmap_start; + free->va_end = vmap_end; + + insert_vmap_area_augment(free, NULL, + &free_vmap_area_root, + &free_vmap_area_list); + } + } +} + void __init vmalloc_init(void) { struct vmap_area *va; struct vm_struct *tmp; int i; + /* + * Create the cache for vmap_area objects. + */ + vmap_area_cachep = KMEM_CACHE(vmap_area, SLAB_PANIC); + for_each_possible_cpu(i) { struct vmap_block_queue *vbq; struct vfree_deferred *p; @@ -1262,16 +1757,21 @@ void __init vmalloc_init(void) /* Import existing vmlist entries. */ for (tmp = vmlist; tmp; tmp = tmp->next) { - va = kzalloc(sizeof(struct vmap_area), GFP_NOWAIT); + va = kmem_cache_zalloc(vmap_area_cachep, GFP_NOWAIT); + if (WARN_ON_ONCE(!va)) + continue; + va->flags = VM_VM_AREA; va->va_start = (unsigned long)tmp->addr; va->va_end = va->va_start + tmp->size; va->vm = tmp; - __insert_vmap_area(va); + insert_vmap_area(va, &vmap_area_root, &vmap_area_list); } - vmap_area_pcpu_hole = VMALLOC_END; - + /* + * Now we can initialize a free vmap space. + */ + vmap_init_free_space(); vmap_initialized = true; } @@ -2375,81 +2875,64 @@ static struct vmap_area *node_to_va(struct rb_node *n) } /** - * pvm_find_next_prev - find the next and prev vmap_area surrounding @end - * @end: target address - * @pnext: out arg for the next vmap_area - * @pprev: out arg for the previous vmap_area + * pvm_find_va_enclose_addr - find the vmap_area @addr belongs to + * @addr: target address * - * Returns: %true if either or both of next and prev are found, - * %false if no vmap_area exists - * - * Find vmap_areas end addresses of which enclose @end. ie. if not - * NULL, *pnext->va_end > @end and *pprev->va_end <= @end. + * Returns: vmap_area if it is found. If there is no such area + * the first highest(reverse order) vmap_area is returned + * i.e. va->va_start < addr && va->va_end < addr or NULL + * if there are no any areas before @addr. */ -static bool pvm_find_next_prev(unsigned long end, - struct vmap_area **pnext, - struct vmap_area **pprev) +static struct vmap_area * +pvm_find_va_enclose_addr(unsigned long addr) { - struct rb_node *n = vmap_area_root.rb_node; - struct vmap_area *va = NULL; + struct vmap_area *va, *tmp; + struct rb_node *n; + + n = free_vmap_area_root.rb_node; + va = NULL; while (n) { - va = rb_entry(n, struct vmap_area, rb_node); - if (end < va->va_end) - n = n->rb_left; - else if (end > va->va_end) + tmp = rb_entry(n, struct vmap_area, rb_node); + if (tmp->va_start <= addr) { + va = tmp; + if (tmp->va_end >= addr) + break; + n = n->rb_right; - else - break; + } else { + n = n->rb_left; + } } - if (!va) - return false; - - if (va->va_end > end) { - *pnext = va; - *pprev = node_to_va(rb_prev(&(*pnext)->rb_node)); - } else { - *pprev = va; - *pnext = node_to_va(rb_next(&(*pprev)->rb_node)); - } - return true; + return va; } /** - * pvm_determine_end - find the highest aligned address between two vmap_areas - * @pnext: in/out arg for the next vmap_area - * @pprev: in/out arg for the previous vmap_area - * @align: alignment - * - * Returns: determined end address + * pvm_determine_end_from_reverse - find the highest aligned address + * of free block below VMALLOC_END + * @va: + * in - the VA we start the search(reverse order); + * out - the VA with the highest aligned end address. * - * Find the highest aligned address between *@pnext and *@pprev below - * VMALLOC_END. *@pnext and *@pprev are adjusted so that the aligned - * down address is between the end addresses of the two vmap_areas. - * - * Please note that the address returned by this function may fall - * inside *@pnext vmap_area. The caller is responsible for checking - * that. + * Returns: determined end address within vmap_area */ -static unsigned long pvm_determine_end(struct vmap_area **pnext, - struct vmap_area **pprev, - unsigned long align) +static unsigned long +pvm_determine_end_from_reverse(struct vmap_area **va, unsigned long align) { - const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1); + unsigned long vmalloc_end = VMALLOC_END & ~(align - 1); unsigned long addr; - if (*pnext) - addr = min((*pnext)->va_start & ~(align - 1), vmalloc_end); - else - addr = vmalloc_end; - - while (*pprev && (*pprev)->va_end > addr) { - *pnext = *pprev; - *pprev = node_to_va(rb_prev(&(*pnext)->rb_node)); + if (likely(*va)) { + list_for_each_entry_from_reverse((*va), + &free_vmap_area_list, list) { + addr = min((*va)->va_end & ~(align - 1), vmalloc_end); + if ((*va)->va_start < addr) + return addr; + } } - return addr; + return 0; } /** @@ -2469,12 +2952,12 @@ static unsigned long pvm_determine_end(struct vmap_area **pnext, * to gigabytes. To avoid interacting with regular vmallocs, these * areas are allocated from top. * - * Despite its complicated look, this allocator is rather simple. It - * does everything top-down and scans areas from the end looking for - * matching slot. While scanning, if any of the areas overlaps with - * existing vmap_area, the base address is pulled down to fit the - * area. Scanning is repeated till all the areas fit and then all - * necessary data structures are inserted and the result is returned. + * Despite its complicated look, this allocator is rather simple. It + * does everything top-down and scans free blocks from the end looking + * for matching base. While scanning, if any of the areas do not fit the + * base address is pulled down to fit the area. Scanning is repeated till + * all the areas fit and then all necessary data structures are inserted + * and the result is returned. */ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, const size_t *sizes, int nr_vms, @@ -2482,11 +2965,12 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, { const unsigned long vmalloc_start = ALIGN(VMALLOC_START, align); const unsigned long vmalloc_end = VMALLOC_END & ~(align - 1); - struct vmap_area **vas, *prev, *next; + struct vmap_area **vas, *va; struct vm_struct **vms; int area, area2, last_area, term_area; - unsigned long base, start, end, last_end; + unsigned long base, start, size, end, last_end; bool purged = false; + enum fit_type type; /* verify parameters and allocate data structures */ BUG_ON(offset_in_page(align) || !is_power_of_2(align)); @@ -2522,7 +3006,7 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, goto err_free2; for (area = 0; area < nr_vms; area++) { - vas[area] = kzalloc(sizeof(struct vmap_area), GFP_KERNEL); + vas[area] = kmem_cache_zalloc(vmap_area_cachep, GFP_KERNEL); vms[area] = kzalloc(sizeof(struct vm_struct), GFP_KERNEL); if (!vas[area] || !vms[area]) goto err_free; @@ -2535,49 +3019,29 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, start = offsets[area]; end = start + sizes[area]; - if (!pvm_find_next_prev(vmap_area_pcpu_hole, &next, &prev)) { - base = vmalloc_end - last_end; - goto found; - } - base = pvm_determine_end(&next, &prev, align) - end; + va = pvm_find_va_enclose_addr(vmalloc_end); + base = pvm_determine_end_from_reverse(&va, align) - end; while (true) { - BUG_ON(next && next->va_end <= base + end); - BUG_ON(prev && prev->va_end > base + end); - /* * base might have underflowed, add last_end before * comparing. */ - if (base + last_end < vmalloc_start + last_end) { - spin_unlock(&vmap_area_lock); - if (!purged) { - purge_vmap_area_lazy(); - purged = true; - goto retry; - } - goto err_free; - } + if (base + last_end < vmalloc_start + last_end) + goto overflow; /* - * If next overlaps, move base downwards so that it's - * right below next and then recheck. + * Fitting base has not been found. */ - if (next && next->va_start < base + end) { - base = pvm_determine_end(&next, &prev, align) - end; - term_area = area; - continue; - } + if (va == NULL) + goto overflow; /* - * If prev overlaps, shift down next and prev and move - * base so that it's right below new next and then - * recheck. + * If this VA does not fit, move base downwards and recheck. */ - if (prev && prev->va_end > base + start) { - next = prev; - prev = node_to_va(rb_prev(&next->rb_node)); - base = pvm_determine_end(&next, &prev, align) - end; + if (base + start < va->va_start || base + end > va->va_end) { + va = node_to_va(rb_prev(&va->rb_node)); + base = pvm_determine_end_from_reverse(&va, align) - end; term_area = area; continue; } @@ -2589,21 +3053,40 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, area = (area + nr_vms - 1) % nr_vms; if (area == term_area) break; + start = offsets[area]; end = start + sizes[area]; - pvm_find_next_prev(base + end, &next, &prev); + va = pvm_find_va_enclose_addr(base + end); } -found: + /* we've found a fitting base, insert all va's */ for (area = 0; area < nr_vms; area++) { - struct vmap_area *va = vas[area]; + int ret; - va->va_start = base + offsets[area]; - va->va_end = va->va_start + sizes[area]; - __insert_vmap_area(va); - } + start = base + offsets[area]; + size = sizes[area]; - vmap_area_pcpu_hole = base + offsets[last_area]; + va = pvm_find_va_enclose_addr(start); + if (WARN_ON_ONCE(va == NULL)) + /* It is a BUG(), but trigger recovery instead. */ + goto recovery; + + type = classify_va_fit_type(va, start, size); + if (WARN_ON_ONCE(type == NOTHING_FIT)) + /* It is a BUG(), but trigger recovery instead. */ + goto recovery; + + ret = adjust_va_to_fit_type(va, start, size, type); + if (unlikely(ret)) + goto recovery; + + /* Allocated area. */ + va = vas[area]; + va->va_start = start; + va->va_end = start + size; + + insert_vmap_area(va, &vmap_area_root, &vmap_area_list); + } spin_unlock(&vmap_area_lock); @@ -2615,9 +3098,38 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, kfree(vas); return vms; +recovery: + /* Remove previously inserted areas. */ + while (area--) { + __free_vmap_area(vas[area]); + vas[area] = NULL; + } + +overflow: + spin_unlock(&vmap_area_lock); + if (!purged) { + purge_vmap_area_lazy(); + purged = true; + + /* Before "retry", check if we recover. */ + for (area = 0; area < nr_vms; area++) { + if (vas[area]) + continue; + + vas[area] = kmem_cache_zalloc( + vmap_area_cachep, GFP_KERNEL); + if (!vas[area]) + goto err_free; + } + + goto retry; + } + err_free: for (area = 0; area < nr_vms; area++) { - kfree(vas[area]); + if (vas[area]) + kmem_cache_free(vmap_area_cachep, vas[area]); + kfree(vms[area]); } err_free2: -- 1.8.3

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[PATCH] tmpfs: separate inode number space for each superblock
by Yang Yingliang 14 Apr '20

14 Apr '20

From: zhengbin <zhengbin13(a)huawei.com> hulk inclusion category: bugfix bugzilla: 16611 CVE: NA --------------------------- The last_ino is unsigned int, who is easy to wrap. Like google, for tmpfs, separate inode number space for each superblock, and change inode number type to unsigned long. see details on https://patchwork.kernel.org/patch/11254001 Signed-off-by: zhengbin <zhengbin13(a)huawei.com> Reviewed-by: zhangyi (F) <yi.zhang(a)huawei.com> Signed-off-by: Yang Yingliang <yangyingliang(a)huawei.com> --- include/linux/shmem_fs.h | 2 ++ mm/shmem.c | 41 ++++++++++++++++++++++++++++++++++++++++- 2 files changed, 42 insertions(+), 1 deletion(-) diff --git a/include/linux/shmem_fs.h b/include/linux/shmem_fs.h index f155dc6..559cd51 100644 --- a/include/linux/shmem_fs.h +++ b/include/linux/shmem_fs.h @@ -38,6 +38,8 @@ struct shmem_sb_info { spinlock_t shrinklist_lock; /* Protects shrinklist */ struct list_head shrinklist; /* List of shinkable inodes */ unsigned long shrinklist_len; /* Length of shrinklist */ + unsigned long __percpu *last_ino_number; /* Last inode number */ + atomic64_t shared_last_ino_number; /* Shared last inode number */ }; static inline struct shmem_inode_info *SHMEM_I(struct inode *inode) diff --git a/mm/shmem.c b/mm/shmem.c index 5b93877..114a2b3 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2207,6 +2207,40 @@ static int shmem_mmap(struct file *file, struct vm_area_struct *vma) return 0; } +#define SHMEM_LAST_INO_BATCH 1024 + +static unsigned long shmem_get_next_ino(struct shmem_sb_info *sbinfo) +{ + unsigned long *p; + unsigned long res; + int cpu; + + cpu = get_cpu(); + p = per_cpu_ptr(sbinfo->last_ino_number, cpu); + res = *p; + +#ifdef CONFIG_SMP + if (unlikely((res & (SHMEM_LAST_INO_BATCH-1)) == 0)) { + /* + * If OS is 32-bit, next will be truncated(Cause + * inode->i_ino is unsigned long, define next to long.) + */ + long next = atomic64_add_return(SHMEM_LAST_INO_BATCH, + &sbinfo->shared_last_ino_number); + + res = next - SHMEM_LAST_INO_BATCH; + } +#endif + + res++; + /* Avoid 0 in the low 32 bits: might appear deleted */ + if (unlikely(!(unsigned int)res)) + res++; + *p = res; + put_cpu(); + return res; +} + static struct inode *shmem_get_inode(struct super_block *sb, const struct inode *dir, umode_t mode, dev_t dev, unsigned long flags) { @@ -2219,7 +2253,7 @@ static struct inode *shmem_get_inode(struct super_block *sb, const struct inode inode = new_inode(sb); if (inode) { - inode->i_ino = get_next_ino(); + inode->i_ino = shmem_get_next_ino(sbinfo); inode_init_owner(inode, dir, mode); inode->i_blocks = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode); @@ -3534,6 +3568,7 @@ static void shmem_put_super(struct super_block *sb) { struct shmem_sb_info *sbinfo = SHMEM_SB(sb); + free_percpu(sbinfo->last_ino_number); percpu_counter_destroy(&sbinfo->used_blocks); mpol_put(sbinfo->mpol); kfree(sbinfo); @@ -3582,6 +3617,10 @@ int shmem_fill_super(struct super_block *sb, void *data, int silent) spin_lock_init(&sbinfo->stat_lock); if (percpu_counter_init(&sbinfo->used_blocks, 0, GFP_KERNEL)) goto failed; + sbinfo->last_ino_number = alloc_percpu(unsigned long); + if (!sbinfo->last_ino_number) + goto failed; + atomic64_set(&sbinfo->shared_last_ino_number, 0); sbinfo->free_inodes = sbinfo->max_inodes; spin_lock_init(&sbinfo->shrinklist_lock); INIT_LIST_HEAD(&sbinfo->shrinklist); -- 1.8.3

1 0

[PATCH 0/6] Support MPAM ACPI
by Wang ShaoBo 14 Apr '20

14 Apr '20

hulk inclusion category: feature bugzilla: 28055 CVE: NA ------------------------------ MPAM driver temporarily force initializing cache/memory unwillingly, Futher We should make it compatible with P2, P4, P6 machine in the future, it's eager to introduce new method to get MSCs' info from BIOS/DT. Note arm hasn't reached a final conclusion about MPAM ACPI Description, BIOS implemented one temporary version according to v1 spec. MPAM ACPI Table organized as follow: *******Address increased by raw******** [DIE0] Memory node: mc[proximity:0] [DIE1] Memory node: mc[proximity:1] [DIE0] Memory node: mc[proximity:0] [DIE2] Memory node: mc[proximity:2] [DIE3] Memory node: mc[proximity:3] [DIE0] Cache node: cache[PPTT_ref:$a] [PARTITION0] Cache node: cache[PPTT_ref:$a] [PARTITION1] Cache node: cache[PPTT_ref:$a] [PARTITION2] Cache node: cache[PPTT_ref:$a] [PARTITION3] Cache node: cache[PPTT_ref:$a] [PARTITION4] Cache node: cache[PPTT_ref:$a] [PARTITION5] Cache node: cache[PPTT_ref:$a] [PARTITION6] Cache node: cache[PPTT_ref:$a] [PARTITION7] Cache node: cache[PPTT_ref:$a] [DIE1] Cache node: cache[PPTT_ref:$b] [PARTITION0] Cache node: cache[PPTT_ref:$b] [PARTITION1] Cache node: cache[PPTT_ref:$b] ... We use PPTT_ref to decide which DIE the cache node belongs to, and use proximity to decide memory node. it is tricky, but still usefull. James Morse (3): ACPI / processor: Add helper to convert acpi_id to a phys_cpuid ACPI / PPTT: Add helper to validate cache nodes from an offset [dead] ACPI / PPTT: Filthy hack to find _a_ backwards reference in the PPTT [ROTTEN] Wang ShaoBo (3): ACPI / PPTT: cacheinfo: Label caches based on fw_token ACPI 6.x: Add definitions for MPAM table MPAM / ACPI: Refactoring MPAM init process and set MPAM ACPI as entrance arch/arm64/Kconfig | 2 + arch/arm64/include/asm/acpi.h | 4 + arch/arm64/include/asm/mpam_resource.h | 15 +- arch/arm64/include/asm/mpam_sched.h | 8 +- arch/arm64/kernel/mpam.c | 246 ++++++++++++++++++------ drivers/acpi/arm64/Kconfig | 3 + drivers/acpi/arm64/Makefile | 1 + drivers/acpi/arm64/mpam.c | 249 +++++++++++++++++++++++++ drivers/acpi/pptt.c | 143 ++++++++++++++ drivers/acpi/processor_core.c | 16 ++ include/acpi/actbl2.h | 58 ++++++ include/acpi/processor.h | 1 + include/linux/acpi.h | 8 + 13 files changed, 698 insertions(+), 56 deletions(-) create mode 100644 drivers/acpi/arm64/mpam.c -- 2.20.1

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关于nvme驱动可靠性优化合入open euler事宜
by Lengchao 13 Apr '20

13 Apr '20

背景说明： NVMe over fabric是存储协议应用的发展方向，业界存储主流厂商均已经发布支持的产品，在测试验证过程中发现一些可靠性问题：基于RHEL/CENT OS 8.0发现如下一些问题： 1、反复闪断端口，主机出现死锁，导致nvme controller卡住，无法恢复，需要重启才能恢复； 2、反复重启存储端服务，主机端crash； 3、通过命令行进行delete controller时导致crash（在nvme over roce连接已经断开时），进行reset controller时导致死锁，controller不能恢复需要重启才能恢复。（在nvme over roce连接已经断开时） 4、 Nvme对于错误码处理考虑不是很完善，在多个不同主机同时对一个存储大压力情况下，存储端需要回复类似busy错误码，在有多路径（DM-Multipath）的情况下会直接向上返回错误码，由于多条路径均返回错误码，导致业务中断或IO归零。 PS：多路径是存储应用必配的。 5、 Nvme 原生多路径对于路径识别采用的机制和传统的多路径软件识别路径方式不同，对于双活支持不友好。PS：双活是存储高可靠应用的典型应用场景。 PS：1、2、3中的问题有多个，其中已经确定部分问题开源社区最新版本已经解决，部分问题未解决，还有部分问题正在分析中； RHEL/CENT OS 8.0内核版本是4.18，open euler最新发布版本的内核版本是4.19，从初步的分析来看，以上问题在open euler均存在。诉求： 1、已经合入社区最新版本的问题，能够快速合入open euler下一个发布版本； 2、对于社区未解决的问题，能够快速推动合入社区，并合入open euler下一个发布版本； 3、针对上述第4、5项，nvme驱动如何优化，并推动合入社区； Open euler对nvme驱动可靠性优化合入的计划是什么样的，如何深度合作快速推动？非常感谢！

2 1