The .of_edma_xlate() function always sets the hw_triggered flag to
true. This causes sw triggered channels consumed via the device-tree
to not function properly, as the driver incorrectly assumes they are
hw triggered. Modify the xlate() function to correctly set the
hw_triggered flag to false for channels reserved for memcpy
operation (ie, sw triggered).
Signed-off-by: Matthew Majewski <mattwmajewski@gmail.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20250216214741.207538-1-mattwmajewski@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The SoC DMA resources for UDMA, BCDMA and PKTDMA can be described via a
combination of up to two resource ranges. The first resource range handles
the default partitioning wherein all resources belonging to that range are
allocated to a single entity and form a continuous range. For use-cases
where the resources are shared across multiple entities and require to be
described via discontinuous ranges, a second resource range is required.
Currently, udma_setup_resources() supports handling resources that belong
to the second range. Extend bcdma_setup_resources() and
pktdma_setup_resources() to support the same.
Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20250205121805.316792-1-s-vadapalli@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
There is kernel dump when do module test:
sysfs: cannot create duplicate filename
/devices/platform/soc@0/44000000.bus/44000000.dma-controller/dma/dma0chan0
__dma_async_device_channel_register+0x128/0x19c
dma_async_device_register+0x150/0x454
fsl_edma_probe+0x6cc/0x8a0
platform_probe+0x68/0xc8
fsl_edma_cleanup_vchan will unlink vchan.chan.device_node, while
dma_async_device_unregister needs the link to do
__dma_async_device_channel_unregister. So need move fsl_edma_cleanup_vchan
after dma_async_device_unregister to make sure channel could be freed.
So clean up chan after dma_async_device_unregister to address this.
Fixes: 6f93b93b2a ("dmaengine: fsl-edma: kill the tasklets upon exit")
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Link: https://lore.kernel.org/r/20250228071720.3780479-1-peng.fan@oss.nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
A RISC-V platform can have both DMA coherent/noncoherent devices.
Since the RISC-V architecture is marked coherent, devices should
be marked as noncoherent when coherent devices exist.
Add dma-noncoherent property for snps,dw-axi-dmac device. It will
be used on SG2044, and it has other coherent devices.
Signed-off-by: Inochi Amaoto <inochiama@gmail.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20250303065649.937233-1-inochiama@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
The user of k3_udma_glue_reset_rx_chn() e.g. ti_am65_cpsw_nuss can
run on multiple platforms having different DMA architectures.
On some platforms there can be one FDQ for all flows in the RX channel
while for others there is a separate FDQ for each flow in the RX channel.
So far we have been relying on the skip_fdq argument of
k3_udma_glue_reset_rx_chn().
Instead of relying on the user to provide this information, infer it
based on DMA architecture during k3_udma_glue_request_rx_chn() and save it
in an internal flag 'single_fdq'. Use that flag at
k3_udma_glue_reset_rx_chn() to deicide if the FDQ needs
to be cleared for every flow or just for flow 0.
Fixes the below issue on ti_am65_cpsw_nuss driver on AM62-SK.
> ip link set eth1 down
> ip link set eth0 down
> ethtool -L eth0 rx 8
> ip link set eth0 up
> modprobe -r ti_am65_cpsw_nuss
[ 103.045726] ------------[ cut here ]------------
[ 103.050505] k3_knav_desc_pool size 512000 != avail 64000
[ 103.050703] WARNING: CPU: 1 PID: 450 at drivers/net/ethernet/ti/k3-cppi-desc-pool.c:33 k3_cppi_desc_pool_destroy+0xa0/0xa8 [k3_cppi_desc_pool]
[ 103.068810] Modules linked in: ti_am65_cpsw_nuss(-) k3_cppi_desc_pool snd_soc_hdmi_codec crct10dif_ce snd_soc_simple_card snd_soc_simple_card_utils display_connector rtc_ti_k3 k3_j72xx_bandgap tidss drm_client_lib snd_soc_davinci_mcas
p drm_dma_helper tps6598x phylink snd_soc_ti_udma rti_wdt drm_display_helper snd_soc_tlv320aic3x_i2c typec at24 phy_gmii_sel snd_soc_ti_edma snd_soc_tlv320aic3x sii902x snd_soc_ti_sdma sa2ul omap_mailbox drm_kms_helper authenc cfg80211 r
fkill fuse drm drm_panel_orientation_quirks backlight ip_tables x_tables ipv6 [last unloaded: k3_cppi_desc_pool]
[ 103.119950] CPU: 1 UID: 0 PID: 450 Comm: modprobe Not tainted 6.13.0-rc7-00001-g9c5e3435fa66 #1011
[ 103.119968] Hardware name: Texas Instruments AM625 SK (DT)
[ 103.119974] pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[ 103.119983] pc : k3_cppi_desc_pool_destroy+0xa0/0xa8 [k3_cppi_desc_pool]
[ 103.148007] lr : k3_cppi_desc_pool_destroy+0xa0/0xa8 [k3_cppi_desc_pool]
[ 103.154709] sp : ffff8000826ebbc0
[ 103.158015] x29: ffff8000826ebbc0 x28: ffff0000090b6300 x27: 0000000000000000
[ 103.165145] x26: 0000000000000000 x25: 0000000000000000 x24: ffff0000019df6b0
[ 103.172271] x23: ffff0000019df6b8 x22: ffff0000019df410 x21: ffff8000826ebc88
[ 103.179397] x20: 000000000007d000 x19: ffff00000a3b3000 x18: 0000000000000000
[ 103.186522] x17: 0000000000000000 x16: 0000000000000000 x15: 000001e8c35e1cde
[ 103.193647] x14: 0000000000000396 x13: 000000000000035c x12: 0000000000000000
[ 103.200772] x11: 000000000000003a x10: 00000000000009c0 x9 : ffff8000826eba20
[ 103.207897] x8 : ffff0000090b6d20 x7 : ffff00007728c180 x6 : ffff00007728c100
[ 103.215022] x5 : 0000000000000001 x4 : ffff000000508a50 x3 : ffff7ffff6146000
[ 103.222147] x2 : 0000000000000000 x1 : e300b4173ee6b200 x0 : 0000000000000000
[ 103.229274] Call trace:
[ 103.231714] k3_cppi_desc_pool_destroy+0xa0/0xa8 [k3_cppi_desc_pool] (P)
[ 103.238408] am65_cpsw_nuss_free_rx_chns+0x28/0x4c [ti_am65_cpsw_nuss]
[ 103.244942] devm_action_release+0x14/0x20
[ 103.249040] release_nodes+0x3c/0x68
[ 103.252610] devres_release_all+0x8c/0xdc
[ 103.256614] device_unbind_cleanup+0x18/0x60
[ 103.260876] device_release_driver_internal+0xf8/0x178
[ 103.266004] driver_detach+0x50/0x9c
[ 103.269571] bus_remove_driver+0x6c/0xbc
[ 103.273485] driver_unregister+0x30/0x60
[ 103.277401] platform_driver_unregister+0x14/0x20
[ 103.282096] am65_cpsw_nuss_driver_exit+0x18/0xff4 [ti_am65_cpsw_nuss]
[ 103.288620] __arm64_sys_delete_module+0x17c/0x25c
[ 103.293404] invoke_syscall+0x44/0x100
[ 103.297149] el0_svc_common.constprop.0+0xc0/0xe0
[ 103.301845] do_el0_svc+0x1c/0x28
[ 103.305155] el0_svc+0x28/0x98
[ 103.308207] el0t_64_sync_handler+0xc8/0xcc
[ 103.312384] el0t_64_sync+0x198/0x19c
[ 103.316040] ---[ end trace 0000000000000000 ]---
Signed-off-by: Roger Quadros <rogerq@kernel.org>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Peter Ujfalusi <peter.ujfalusi@gmail.com>
Link: https://lore.kernel.org/r/20250224-k3-udma-glue-single-fdq-v2-1-cbe7621f2507@kernel.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add support for the i.MX94 DMA controllers. The SoC includes two DMA
controllers: one compatible with i.MX93 eDMA3 and another compatible with
i.MX95 eDMA5.
Add compatible string "fsl,imx94-edma3" with fallback to "fsl,imx93-edma3".
Add compatible string "fsl,imx94-edma5" with fallback to "fsl,imx95-edma5".
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Acked-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250221222153.405285-1-Frank.Li@nxp.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Replace ternary (condition ? "enable" : "disable") syntax with helpers
from string_choices.h because:
1. Simple function call with one argument is easier to read. Ternary
operator has three arguments and with wrapping might lead to quite
long code.
2. Is slightly shorter thus also easier to read.
3. It brings uniformity in the text - same string.
4. Allows deduping by the linker, which results in a smaller binary
file.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> #dw-edma
Reviewed-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Link: https://lore.kernel.org/r/20250114191021.854080-1-krzysztof.kozlowski@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Add a description, required properties, appropriate compatibles and
missing properties like clocks and clock-names which are not defined in
the text binding for all the SoCs that are supported by microchip.
Update the text binding name `atmel-dma.txt` to
`atmel,at91sam9g45-dma.yaml` for the files which reference to
`atmel-dma.txt`. Drop Tudor name from maintainers.
Signed-off-by: Durai Manickam KR <durai.manickamkr@microchip.com>
Signed-off-by: Charan Pedumuru <charan.pedumuru@microchip.com>
Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
Link: https://lore.kernel.org/r/20250203-test-v4-1-a9ec3eded1c7@microchip.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Pull turbostat updates from Len Brown:
- Fix regression that affinitized forked child in one-shot mode.
- Harden one-shot mode against hotplug online/offline
- Enable RAPL SysWatt column by default
- Add initial PTL, CWF platform support
- Harden initial PMT code in response to early use
- Enable first built-in PMT counter: CWF c1e residency
- Refuse to run on unsupported platforms without --force, to encourage
updating to a version that supports the system, and to avoid
no-so-useful measurement results
* tag 'turbostat-2025.02.02' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux: (25 commits)
tools/power turbostat: version 2025.02.02
tools/power turbostat: Add CPU%c1e BIC for CWF
tools/power turbostat: Harden one-shot mode against cpu offline
tools/power turbostat: Fix forked child affinity regression
tools/power turbostat: Add tcore clock PMT type
tools/power turbostat: version 2025.01.14
tools/power turbostat: Allow adding PMT counters directly by sysfs path
tools/power turbostat: Allow mapping multiple PMT files with the same GUID
tools/power turbostat: Add PMT directory iterator helper
tools/power turbostat: Extend PMT identification with a sequence number
tools/power turbostat: Return default value for unmapped PMT domains
tools/power turbostat: Check for non-zero value when MSR probing
tools/power turbostat: Enhance turbostat self-performance visibility
tools/power turbostat: Add fixed RAPL PSYS divisor for SPR
tools/power turbostat: Fix PMT mmaped file size rounding
tools/power turbostat: Remove SysWatt from DISABLED_BY_DEFAULT
tools/power turbostat: Add an NMI column
tools/power turbostat: add Busy% to "show idle"
tools/power turbostat: Introduce --force parameter
tools/power turbostat: Improve --help output
...
Pull sh updates from John Paul Adrian Glaubitz:
"Fixes and improvements for sh:
- replace seq_printf() with the more efficient
seq_put_decimal_ull_width() to increase performance when stress
reading /proc/interrupts (David Wang)
- migrate sh to the generic rule for built-in DTB to help avoid race
conditions during parallel builds which can occur because Kbuild
decends into arch/*/boot/dts twice (Masahiro Yamada)
- replace select with imply in the board Kconfig for enabling
hardware with complex dependencies. This addresses warnings which
were reported by the kernel test robot (Geert Uytterhoeven)"
* tag 'sh-for-v6.14-tag1' of git://git.kernel.org/pub/scm/linux/kernel/git/glaubitz/sh-linux:
sh: boards: Use imply to enable hardware with complex dependencies
sh: Migrate to the generic rule for built-in DTB
sh: irq: Use seq_put_decimal_ull_width() for decimal values
Summary of Changes since 2024.11.30:
Fix regression in 2023.11.07 that affinitized forked child
in one-shot mode.
Harden one-shot mode against hotplug online/offline
Enable RAPL SysWatt column by default.
Add initial PTL, CWF platform support.
Harden initial PMT code in response to early use.
Enable first built-in PMT counter: CWF c1e residency
Refuse to run on unsupported platforms without --force,
to encourage updating to a version that supports the system,
and to avoid no-so-useful measurement results.
Signed-off-by: Len Brown <len.brown@intel.com>
Pull misc vfs cleanups from Al Viro:
"Two unrelated patches - one is a removal of long-obsolete include in
overlayfs (it used to need fs/internal.h, but the extern it wanted has
been moved back to include/linux/namei.h) and another introduces
convenience helper constructing struct qstr by a NUL-terminated
string"
* tag 'pull-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
add a string-to-qstr constructor
fs/overlayfs/namei.c: get rid of include ../internal.h
Pull MIPS fix from Thomas Bogendoerfer:
"Revert commit breaking sysv ipc for o32 ABI"
* tag 'mips_6.14_1' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
Revert "mips: fix shmctl/semctl/msgctl syscall for o32"
Pull more smb client updates from Steve French:
- various updates for special file handling: symlink handling,
support for creating sockets, cleanups, new mount options (e.g. to
allow disabling using reparse points for them, and to allow
overriding the way symlinks are saved), and fixes to error paths
- fix for kerberos mounts (allow IAKerb)
- SMB1 fix for stat and for setting SACL (auditing)
- fix an incorrect error code mapping
- cleanups"
* tag 'v6.14-rc-smb3-client-fixes-part2' of git://git.samba.org/sfrench/cifs-2.6: (21 commits)
cifs: Fix parsing native symlinks directory/file type
cifs: update internal version number
cifs: Add support for creating WSL-style symlinks
smb3: add support for IAKerb
cifs: Fix struct FILE_ALL_INFO
cifs: Add support for creating NFS-style symlinks
cifs: Add support for creating native Windows sockets
cifs: Add mount option -o reparse=none
cifs: Add mount option -o symlink= for choosing symlink create type
cifs: Fix creating and resolving absolute NT-style symlinks
cifs: Simplify reparse point check in cifs_query_path_info() function
cifs: Remove symlink member from cifs_open_info_data union
cifs: Update description about ACL permissions
cifs: Rename struct reparse_posix_data to reparse_nfs_data_buffer and move to common/smb2pdu.h
cifs: Remove struct reparse_posix_data from struct cifs_open_info_data
cifs: Remove unicode parameter from parse_reparse_point() function
cifs: Fix getting and setting SACLs over SMB1
cifs: Remove intermediate object of failed create SFU call
cifs: Validate EAs for WSL reparse points
cifs: Change translation of STATUS_PRIVILEGE_NOT_HELD to -EPERM
...
Pull debugfs fix from Greg KH:
"Here is a single debugfs fix from Al to resolve a reported regression
in the driver-core tree. It has been reported to fix the issue"
* tag 'driver-core-6.14-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
debugfs: Fix the missing initializations in __debugfs_file_get()
Pull misc fixes from Andrew Morton:
"21 hotfixes. 8 are cc:stable and the remainder address post-6.13
issues. 13 are for MM and 8 are for non-MM.
All are singletons, please see the changelogs for details"
* tag 'mm-hotfixes-stable-2025-02-01-03-56' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (21 commits)
MAINTAINERS: include linux-mm for xarray maintenance
revert "xarray: port tests to kunit"
MAINTAINERS: add lib/test_xarray.c
mailmap, MAINTAINERS, docs: update Carlos's email address
mm/hugetlb: fix hugepage allocation for interleaved memory nodes
mm: gup: fix infinite loop within __get_longterm_locked
mm, swap: fix reclaim offset calculation error during allocation
.mailmap: update email address for Christopher Obbard
kfence: skip __GFP_THISNODE allocations on NUMA systems
nilfs2: fix possible int overflows in nilfs_fiemap()
mm: compaction: use the proper flag to determine watermarks
kernel: be more careful about dup_mmap() failures and uprobe registering
mm/fake-numa: handle cases with no SRAT info
mm: kmemleak: fix upper boundary check for physical address objects
mailmap: add an entry for Hamza Mahfooz
MAINTAINERS: mailmap: update Yosry Ahmed's email address
scripts/gdb: fix aarch64 userspace detection in get_current_task
mm/vmscan: accumulate nr_demoted for accurate demotion statistics
ocfs2: fix incorrect CPU endianness conversion causing mount failure
mm/zsmalloc: add __maybe_unused attribute for is_first_zpdesc()
...
Pull media fix from Mauro Carvalho Chehab:
"A revert for a regression in the uvcvideo driver"
* tag 'media/v6.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
Revert "media: uvcvideo: Require entities to have a non-zero unique ID"
gather_bootmem_prealloc() assumes the start nid as 0 and size as
num_node_state(N_MEMORY). That means in case if memory attached numa
nodes are interleaved, then gather_bootmem_prealloc_parallel() will fail
to scan few of these nodes.
Since memory attached numa nodes can be interleaved in any fashion, hence
ensure that the current code checks for all numa node ids
(.size = nr_node_ids). Let's still keep max_threads as N_MEMORY, so that
it can distributes all nr_node_ids among the these many no. threads.
e.g. qemu cmdline
========================
numa_cmd="-numa node,nodeid=1,memdev=mem1,cpus=2-3 -numa node,nodeid=0,cpus=0-1 -numa dist,src=0,dst=1,val=20"
mem_cmd="-object memory-backend-ram,id=mem1,size=16G"
w/o this patch for cmdline (default_hugepagesz=1GB hugepagesz=1GB hugepages=2):
==========================
~ # cat /proc/meminfo |grep -i huge
AnonHugePages: 0 kB
ShmemHugePages: 0 kB
FileHugePages: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 1048576 kB
Hugetlb: 0 kB
with this patch for cmdline (default_hugepagesz=1GB hugepagesz=1GB hugepages=2):
===========================
~ # cat /proc/meminfo |grep -i huge
AnonHugePages: 0 kB
ShmemHugePages: 0 kB
FileHugePages: 0 kB
HugePages_Total: 2
HugePages_Free: 2
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 1048576 kB
Hugetlb: 2097152 kB
Link: https://lkml.kernel.org/r/f8d8dad3a5471d284f54185f65d575a6aaab692b.1736592534.git.ritesh.list@gmail.com
Fixes: b78b27d029 ("hugetlb: parallelize 1G hugetlb initialization")
Signed-off-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Reported-by: Pavithra Prakash <pavrampu@linux.ibm.com>
Suggested-by: Muchun Song <muchun.song@linux.dev>
Tested-by: Sourabh Jain <sourabhjain@linux.ibm.com>
Reviewed-by: Luiz Capitulino <luizcap@redhat.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Donet Tom <donettom@linux.ibm.com>
Cc: Gang Li <gang.li@linux.dev>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Since nilfs_bmap_lookup_contig() in nilfs_fiemap() calculates its result
by being prepared to go through potentially maxblocks == INT_MAX blocks,
the value in n may experience an overflow caused by left shift of blkbits.
While it is extremely unlikely to occur, play it safe and cast right hand
expression to wider type to mitigate the issue.
Found by Linux Verification Center (linuxtesting.org) with static analysis
tool SVACE.
Link: https://lkml.kernel.org/r/20250124222133.5323-1-konishi.ryusuke@gmail.com
Fixes: 622daaff0a ("nilfs2: fiemap support")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There are 4 NUMA nodes on my machine, and each NUMA node has 32GB of
memory. I have configured 16GB of CMA memory on each NUMA node, and
starting a 32GB virtual machine with device passthrough is extremely slow,
taking almost an hour.
Long term GUP cannot allocate memory from CMA area, so a maximum of 16 GB
of no-CMA memory on a NUMA node can be used as virtual machine memory.
There is 16GB of free CMA memory on a NUMA node, which is sufficient to
pass the order-0 watermark check, causing the __compaction_suitable()
function to consistently return true.
For costly allocations, if the __compaction_suitable() function always
returns true, it causes the __alloc_pages_slowpath() function to fail to
exit at the appropriate point. This prevents timely fallback to
allocating memory on other nodes, ultimately resulting in excessively long
virtual machine startup times.
Call trace:
__alloc_pages_slowpath
if (compact_result == COMPACT_SKIPPED ||
compact_result == COMPACT_DEFERRED)
goto nopage; // should exit __alloc_pages_slowpath() from here
We could use the real unmovable allocation context to have
__zone_watermark_unusable_free() subtract CMA pages, and thus we won't
pass the order-0 check anymore once the non-CMA part is exhausted. There
is some risk that in some different scenario the compaction could in fact
migrate pages from the exhausted non-CMA part of the zone to the CMA part
and succeed, and we'll skip it instead. But only __GFP_NORETRY
allocations should be affected in the immediate "goto nopage" when
compaction is skipped, others will attempt with DEF_COMPACT_PRIORITY
anyway and won't fail without trying to compact-migrate the non-CMA
pageblocks into CMA pageblocks first, so it should be fine.
After this fix, it only takes a few tens of seconds to start a 32GB
virtual machine with device passthrough functionality.
Link: https://lore.kernel.org/lkml/1736335854-548-1-git-send-email-yangge1116@126.com/
Link: https://lkml.kernel.org/r/1737788037-8439-1-git-send-email-yangge1116@126.com
Signed-off-by: yangge <yangge1116@126.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Barry Song <21cnbao@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If a memory allocation fails during dup_mmap(), the maple tree can be left
in an unsafe state for other iterators besides the exit path. All the
locks are dropped before the exit_mmap() call (in mm/mmap.c), but the
incomplete mm_struct can be reached through (at least) the rmap finding
the vmas which have a pointer back to the mm_struct.
Up to this point, there have been no issues with being able to find an
mm_struct that was only partially initialised. Syzbot was able to make
the incomplete mm_struct fail with recent forking changes, so it has been
proven unsafe to use the mm_struct that hasn't been initialised, as
referenced in the link below.
Although 8ac662f5da ("fork: avoid inappropriate uprobe access to
invalid mm") fixed the uprobe access, it does not completely remove the
race.
This patch sets the MMF_OOM_SKIP to avoid the iteration of the vmas on the
oom side (even though this is extremely unlikely to be selected as an oom
victim in the race window), and sets MMF_UNSTABLE to avoid other potential
users from using a partially initialised mm_struct.
When registering vmas for uprobe, skip the vmas in an mm that is marked
unstable. Modifying a vma in an unstable mm may cause issues if the mm
isn't fully initialised.
Link: https://lore.kernel.org/all/6756d273.050a0220.2477f.003d.GAE@google.com/
Link: https://lkml.kernel.org/r/20250127170221.1761366-1-Liam.Howlett@oracle.com
Fixes: d240629148 ("fork: use __mt_dup() to duplicate maple tree in dup_mmap()")
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Peng Zhang <zhangpeng.00@bytedance.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
