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gendwarfksyms: Add a separate pass to resolve FQNs#54

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gendwarfksyms: Add a separate pass to resolve FQNs#54
modules-kpd-app[bot] wants to merge 1 commit intomodules-next_basefrom
series/930207=>modules-next

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@modules-kpd-app modules-kpd-app bot commented Feb 3, 2025

Pull request for series with
subject: gendwarfksyms: Add a separate pass to resolve FQNs
version: 1
url: https://patchwork.kernel.org/project/linux-modules/list/?series=930207

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modules-kpd-app bot commented Feb 3, 2025

Upstream branch: 48ecfdd
series: https://patchwork.kernel.org/project/linux-modules/list/?series=930207
version: 1

Pull request is NOT updated. Failed to apply https://patchwork.kernel.org/project/linux-modules/list/?series=930207
error message:

Cmd('git') failed due to: exit code(128)
  cmdline: git am --3way
  stdout: 'Applying: gendwarfksyms: Add a separate pass to resolve FQNs
Using index info to reconstruct a base tree...
A	scripts/gendwarfksyms/die.c
A	scripts/gendwarfksyms/dwarf.c
A	scripts/gendwarfksyms/gendwarfksyms.h
A	scripts/gendwarfksyms/types.c
Falling back to patching base and 3-way merge...
CONFLICT (modify/delete): scripts/gendwarfksyms/types.c deleted in HEAD and modified in gendwarfksyms: Add a separate pass to resolve FQNs. Version gendwarfksyms: Add a separate pass to resolve FQNs of scripts/gendwarfksyms/types.c left in tree.
CONFLICT (modify/delete): scripts/gendwarfksyms/gendwarfksyms.h deleted in HEAD and modified in gendwarfksyms: Add a separate pass to resolve FQNs. Version gendwarfksyms: Add a separate pass to resolve FQNs of scripts/gendwarfksyms/gendwarfksyms.h left in tree.
CONFLICT (modify/delete): scripts/gendwarfksyms/dwarf.c deleted in HEAD and modified in gendwarfksyms: Add a separate pass to resolve FQNs. Version gendwarfksyms: Add a separate pass to resolve FQNs of scripts/gendwarfksyms/dwarf.c left in tree.
CONFLICT (modify/delete): scripts/gendwarfksyms/die.c deleted in HEAD and modified in gendwarfksyms: Add a separate pass to resolve FQNs. Version gendwarfksyms: Add a separate pass to resolve FQNs of scripts/gendwarfksyms/die.c left in tree.
Patch failed at 0001 gendwarfksyms: Add a separate pass to resolve FQNs'
  stderr: 'error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config advice.mergeConflict false"'

conflict:

* Unmerged path scripts/gendwarfksyms/die.c
* Unmerged path scripts/gendwarfksyms/dwarf.c
* Unmerged path scripts/gendwarfksyms/gendwarfksyms.h
* Unmerged path scripts/gendwarfksyms/types.c

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modules-kpd-app bot commented Feb 4, 2025

Upstream branch: 053842e
series: https://patchwork.kernel.org/project/linux-modules/list/?series=930207
version: 1

@modules-kpd-app modules-kpd-app bot force-pushed the series/930207=>modules-next branch from e3033ae to b3190f5 Compare February 4, 2025 12:19
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modules-kpd-app bot commented Feb 17, 2025

Upstream branch: afa9286
series: https://patchwork.kernel.org/project/linux-modules/list/?series=930207
version: 1

@samitolvanen @mcgrof
gendwarfksyms: Add a separate pass to resolve FQNs
9f5093d 
Using dwarf_getscopes_die to resolve fully-qualified names turns out to
be rather slow, and also results in duplicate scopes being processed,
which doesn't help. Simply adding an extra pass to resolve names for all
DIEs before processing exports is noticeably faster.

For the object files with the most exports in a defconfig+Rust build,
the performance improvement is consistently >50%:

rust/bindings.o: 1038 exports
    before: 9.5980 +- 0.0183 seconds time elapsed  ( +-  0.19% )
     after: 4.3116 +- 0.0287 seconds time elapsed  ( +-  0.67% )

rust/core.o: 424 exports
    before: 5.3584 +- 0.0204 seconds time elapsed  ( +-  0.38% )
     after: 0.05348 +- 0.00129 seconds time elapsed  ( +-  2.42% )
            ^ Not a mistake.

net/core/dev.o: 190 exports
    before: 9.0507 +- 0.0297 seconds time elapsed  ( +-  0.33% )
     after: 3.2882 +- 0.0165 seconds time elapsed  ( +-  0.50% )

rust/kernel.o: 129 exports
    before: 6.8571 +- 0.0317 seconds time elapsed  ( +-  0.46% )
     after: 2.9096 +- 0.0316 seconds time elapsed  ( +-  1.09% )

net/core/skbuff.o: 120 exports
    before: 5.4805 +- 0.0291 seconds time elapsed  ( +-  0.53% )
     after: 2.0339 +- 0.0231 seconds time elapsed  ( +-  1.14% )

drivers/gpu/drm/display/drm_dp_helper.o: 101 exports
    before: 1.7877 +- 0.0187 seconds time elapsed  ( +-  1.05% )
     after: 0.69245 +- 0.00994 seconds time elapsed  ( +-  1.44% )

net/core/sock.o: 97 exports
    before: 5.8327 +- 0.0653 seconds time elapsed  ( +-  1.12% )
     after: 2.0784 +- 0.0291 seconds time elapsed  ( +-  1.40% )

drivers/net/phy/phy_device.o: 95 exports
    before: 3.0671 +- 0.0371 seconds time elapsed  ( +-  1.21% )
     after: 1.2127 +- 0.0207 seconds time elapsed  ( +-  1.70% )

drivers/pci/pci.o: 93 exports
    before: 1.1130 +- 0.0113 seconds time elapsed  ( +-  1.01% )
     after: 0.4848 +- 0.0127 seconds time elapsed  ( +-  2.63% )

kernel/sched/core.o: 83 exports
    before: 3.5092 +- 0.0223 seconds time elapsed  ( +-  0.64% )
     after: 1.1231 +- 0.0145 seconds time elapsed  ( +-  1.29% )

Overall, a defconfig+DWARF5 build with gendwarfksyms and Rust is 14.8%
faster with this patch applied on my test system. Without Rust, there's
still a 10.4% improvement in build time when gendwarfksyms is used.

Note that symbol versions are unchanged with this patch.

Suggested-by: Giuliano Procida <gprocida@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
@modules-kpd-app modules-kpd-app bot force-pushed the series/930207=>modules-next branch from b3190f5 to 9f5093d Compare February 17, 2025 10:02
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modules-kpd-app bot commented Feb 17, 2025

At least one diff in series https://patchwork.kernel.org/project/linux-modules/list/?series=930207 irrelevant now. Closing PR.

@modules-kpd-app modules-kpd-app bot closed this Feb 17, 2025
@modules-kpd-app modules-kpd-app bot deleted the series/930207=>modules-next branch February 17, 2025 10:34
dagomez137 pushed a commit that referenced this pull request Sep 8, 2025
@HW-YIN @akpm00
of_numa: fix uninitialized memory nodes causing kernel panic
ee4d098 
When there are memory-only nodes (nodes without CPUs), these nodes are not
properly initialized, causing kernel panic during boot.

of_numa_init
	of_numa_parse_cpu_nodes
		node_set(nid, numa_nodes_parsed);
	of_numa_parse_memory_nodes

In of_numa_parse_cpu_nodes, numa_nodes_parsed gets updated only for nodes
containing CPUs.  Memory-only nodes should have been updated in
of_numa_parse_memory_nodes, but they weren't.

Subsequently, when free_area_init() attempts to access NODE_DATA() for
these uninitialized memory nodes, the kernel panics due to NULL pointer
dereference.

This can be reproduced on ARM64 QEMU with 1 CPU and 2 memory nodes:

qemu-system-aarch64 \
-cpu host -nographic \
-m 4G -smp 1 \
-machine virt,accel=kvm,gic-version=3,iommu=smmuv3 \
-object memory-backend-ram,size=2G,id=mem0 \
-object memory-backend-ram,size=2G,id=mem1 \
-numa node,nodeid=0,memdev=mem0 \
-numa node,nodeid=1,memdev=mem1 \
-kernel $IMAGE \
-hda $DISK \
-append "console=ttyAMA0 root=/dev/vda rw earlycon"

[    0.000000] Booting Linux on physical CPU 0x0000000000 [0x481fd010]
[    0.000000] Linux version 6.17.0-rc1-00001-gabb4b3daf18c-dirty (yintirui@local) (gcc (GCC) 12.3.1, GNU ld (GNU Binutils) 2.41) #52 SMP PREEMPT Mon Aug 18 09:49:40 CST 2025
[    0.000000] KASLR enabled
[    0.000000] random: crng init done
[    0.000000] Machine model: linux,dummy-virt
[    0.000000] efi: UEFI not found.
[    0.000000] earlycon: pl11 at MMIO 0x0000000009000000 (options '')
[    0.000000] printk: legacy bootconsole [pl11] enabled
[    0.000000] OF: reserved mem: Reserved memory: No reserved-memory node in the DT
[    0.000000] NODE_DATA(0) allocated [mem 0xbfffd9c0-0xbfffffff]
[    0.000000] node 1 must be removed before remove section 23
[    0.000000] Zone ranges:
[    0.000000]   DMA      [mem 0x0000000040000000-0x00000000ffffffff]
[    0.000000]   DMA32    empty
[    0.000000]   Normal   [mem 0x0000000100000000-0x000000013fffffff]
[    0.000000] Movable zone start for each node
[    0.000000] Early memory node ranges
[    0.000000]   node   0: [mem 0x0000000040000000-0x00000000bfffffff]
[    0.000000]   node   1: [mem 0x00000000c0000000-0x000000013fffffff]
[    0.000000] Initmem setup node 0 [mem 0x0000000040000000-0x00000000bfffffff]
[    0.000000] Unable to handle kernel NULL pointer dereference at virtual address 00000000000000a0
[    0.000000] Mem abort info:
[    0.000000]   ESR = 0x0000000096000004
[    0.000000]   EC = 0x25: DABT (current EL), IL = 32 bits
[    0.000000]   SET = 0, FnV = 0
[    0.000000]   EA = 0, S1PTW = 0
[    0.000000]   FSC = 0x04: level 0 translation fault
[    0.000000] Data abort info:
[    0.000000]   ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
[    0.000000]   CM = 0, WnR = 0, TnD = 0, TagAccess = 0
[    0.000000]   GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
[    0.000000] [00000000000000a0] user address but active_mm is swapper
[    0.000000] Internal error: Oops: 0000000096000004 [#1]  SMP
[    0.000000] Modules linked in:
[    0.000000] CPU: 0 UID: 0 PID: 0 Comm: swapper Not tainted 6.17.0-rc1-00001-g760c6dabf762-dirty #54 PREEMPT
[    0.000000] Hardware name: linux,dummy-virt (DT)
[    0.000000] pstate: 800000c5 (Nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    0.000000] pc : free_area_init+0x50c/0xf9c
[    0.000000] lr : free_area_init+0x5c0/0xf9c
[    0.000000] sp : ffffa02ca0f33c00
[    0.000000] x29: ffffa02ca0f33cb0 x28: 0000000000000000 x27: 0000000000000000
[    0.000000] x26: 4ec4ec4ec4ec4ec5 x25: 00000000000c0000 x24: 00000000000c0000
[    0.000000] x23: 0000000000040000 x22: 0000000000000000 x21: ffffa02ca0f3b368
[    0.000000] x20: ffffa02ca14c7b98 x19: 0000000000000000 x18: 0000000000000002
[    0.000000] x17: 000000000000cacc x16: 0000000000000001 x15: 0000000000000001
[    0.000000] x14: 0000000080000000 x13: 0000000000000018 x12: 0000000000000002
[    0.000000] x11: ffffa02ca0fd4f00 x10: ffffa02ca14bab20 x9 : ffffa02ca14bab38
[    0.000000] x8 : 00000000000c0000 x7 : 0000000000000001 x6 : 0000000000000002
[    0.000000] x5 : 0000000140000000 x4 : ffffa02ca0f33c90 x3 : ffffa02ca0f33ca0
[    0.000000] x2 : ffffa02ca0f33c98 x1 : 0000000080000000 x0 : 0000000000000001
[    0.000000] Call trace:
[    0.000000]  free_area_init+0x50c/0xf9c (P)
[    0.000000]  bootmem_init+0x110/0x1dc
[    0.000000]  setup_arch+0x278/0x60c
[    0.000000]  start_kernel+0x70/0x748
[    0.000000]  __primary_switched+0x88/0x90
[    0.000000] Code: d503201f b98093e0 52800016 f8607a93 (f9405260)
[    0.000000] ---[ end trace 0000000000000000 ]---
[    0.000000] Kernel panic - not syncing: Attempted to kill the idle task!
[    0.000000] ---[ end Kernel panic - not syncing: Attempted to kill the idle task! ]---

Link: https://lkml.kernel.org/r/20250819075510.2079961-1-yintirui@huawei.com
Fixes: 7675076 ("arch_numa: switch over to numa_memblks")
Signed-off-by: Yin Tirui <yintirui@huawei.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Chen Jun <chenjun102@huawei.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Joanthan Cameron <Jonathan.Cameron@huawei.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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