Peter Xu
fc21d37d4f
UPSTREAM: mm: allow VM_FAULT_RETRY for multiple times ...
The idea comes from a discussion between Linus and Andrea [1].
Before this patch we only allow a page fault to retry once. We achieved
this by clearing the FAULT_FLAG_ALLOW_RETRY flag when doing
handle_mm_fault() the second time. This was majorly used to avoid
unexpected starvation of the system by looping over forever to handle the
page fault on a single page. However that should hardly happen, and after
all for each code path to return a VM_FAULT_RETRY we'll first wait for a
condition (during which time we should possibly yield the cpu) to happen
before VM_FAULT_RETRY is really returned.
This patch removes the restriction by keeping the FAULT_FLAG_ALLOW_RETRY
flag when we receive VM_FAULT_RETRY. It means that the page fault handler
now can retry the page fault for multiple times if necessary without the
need to generate another page fault event. Meanwhile we still keep the
FAULT_FLAG_TRIED flag so page fault handler can still identify whether a
page fault is the first attempt or not.
Then we'll have these combinations of fault flags (only considering
ALLOW_RETRY flag and TRIED flag):
- ALLOW_RETRY and !TRIED: this means the page fault allows to
retry, and this is the first try
- ALLOW_RETRY and TRIED: this means the page fault allows to
retry, and this is not the first try
- !ALLOW_RETRY and !TRIED: this means the page fault does not allow
to retry at all
- !ALLOW_RETRY and TRIED: this is forbidden and should never be used
In existing code we have multiple places that has taken special care of
the first condition above by checking against (fault_flags &
FAULT_FLAG_ALLOW_RETRY). This patch introduces a simple helper to detect
the first retry of a page fault by checking against both (fault_flags &
FAULT_FLAG_ALLOW_RETRY) and !(fault_flag & FAULT_FLAG_TRIED) because now
even the 2nd try will have the ALLOW_RETRY set, then use that helper in
all existing special paths. One example is in __lock_page_or_retry(), now
we'll drop the mmap_sem only in the first attempt of page fault and we'll
keep it in follow up retries, so old locking behavior will be retained.
This will be a nice enhancement for current code [2] at the same time a
supporting material for the future userfaultfd-writeprotect work, since in
that work there will always be an explicit userfault writeprotect retry
for protected pages, and if that cannot resolve the page fault (e.g., when
userfaultfd-writeprotect is used in conjunction with swapped pages) then
we'll possibly need a 3rd retry of the page fault. It might also benefit
other potential users who will have similar requirement like userfault
write-protection.
GUP code is not touched yet and will be covered in follow up patch.
Please read the thread below for more information.
[1] https://lore.kernel.org/lkml/20171102193644.GB22686@redhat.com/
[2] https://lore.kernel.org/lkml/20181230154648.GB9832@redhat.com/
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Brian Geffon <bgeffon@google.com>
Cc: Bobby Powers <bobbypowers@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Denis Plotnikov <dplotnikov@virtuozzo.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Martin Cracauer <cracauer@cons.org>
Cc: Marty McFadden <mcfadden8@llnl.gov>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Maya Gokhale <gokhale2@llnl.gov>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Link: http://lkml.kernel.org/r/20200220160246.9790-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 4064b982706375025628094e51d11cf1a958a5d3)
Bug: 176847924
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Change-Id: If0378d8ccbfc54a574b91103a6dc76e446f5f12e
2025-05-18 08:08:42 +00:00
firmware: meson_sm: Rework driver as a proper platform driver
2024-04-13 12:51:26 +02:00
Merge android11-5.4.249+ ( d57e792) into msm-5.4
2023-09-28 16:45:28 +05:30
RDMA/mlx5: Enforce same type port association for multiport RoCE
2025-01-09 13:23:34 +01:00
mmc: sdhci-msm: Disable partial_init and clk-scaling to avoid RED error
2024-04-18 10:46:06 +05:30
Merge tag 'ASB-2024-12-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2024-12-17 03:24:53 +02:00
Revert "netfilter: Replace zero-length array with flexible-array member"
2025-01-14 17:17:17 +00:00
Revert "netfilter: Replace zero-length array with flexible-array member"
2025-01-14 17:17:17 +00:00
Revert "netfilter: Replace zero-length array with flexible-array member"
2025-01-14 17:17:17 +00:00
Revert "netfilter: Replace zero-length array with flexible-array member"
2025-01-14 17:17:17 +00:00
Revert "netfilter: Replace zero-length array with flexible-array member"
2025-01-14 17:17:17 +00:00
Merge tag 'ASB-2024-10-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2024-10-09 18:08:17 +00:00
This is the 5.4.244 stable release
2023-06-20 11:07:18 +00:00
qed: Improve the stack space of filter_config()
2024-08-19 05:33:30 +02:00
UPSTREAM: mm: return faster for non-fatal signals in user mode faults
2025-05-18 08:08:42 +00:00
soc: qcom: mdt_loader: Read hash from firmware blob
2024-08-08 16:32:23 -05:00
Revert "spi: Fix deadlock when adding SPI controllers on SPI buses"
2024-11-21 22:00:36 +00:00
SUNRPC: Replace internal use of SOCKWQ_ASYNC_NOSPACE
2024-12-14 19:44:42 +01:00
Merge tag 'ASB-2025-03-05_11-5.4' into android13-5.4-lahaina
2025-04-12 09:31:28 +00:00
ACPI/IORT: Make iort_msi_map_rid() PCI agnostic
2023-12-13 18:18:10 +01:00
UPSTREAM: fs: add LSM-supporting anon-inode interface
2025-02-20 04:17:45 +02:00
fix bitmap corruption on close_range() with CLOSE_RANGE_UNSHARE
2024-09-04 13:14:50 +02:00
ocfs2/dlm: move BITS_TO_BYTES() to bitops.h for wider use
2023-06-09 10:28:54 +02:00
Merge 5.4.287 into android11-5.4-lts
2024-12-16 10:50:16 +00:00
Revert "bpf: Add map and need_defer parameters to .map_fd_put_ptr()"
2024-03-05 10:21:38 +00:00
Revert "cgroup: Make operations on the cgroup root_list RCU safe"
2024-12-16 10:50:29 +00:00
Merge android11-5.4.259+ ( 81334f2) into msm-5.4
2023-12-18 15:40:18 +05:30
ftruncate: pass a signed offset
2024-07-05 09:08:31 +02:00
Fix gcc 4.9 build issue in 5.4.y
2024-08-19 05:33:53 +02:00
Merge android11-5.4.254+ ( 91f7025) into msm-5.4
2023-10-30 22:46:41 -07:00
Revert "hrtimers: Push pending hrtimers away from outgoing CPU earlier"
2023-12-18 18:58:40 +00:00
Merge tag 'ASB-2024-10-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2024-10-09 18:08:17 +00:00
Revert "cred: switch to using atomic_long_t"
2024-01-03 17:00:08 +00:00
This is the 5.4.283 stable release
2024-09-06 11:18:13 +00:00
Merge android11-5.4.259+ ( 81334f2) into msm-5.4
2023-12-18 15:40:18 +05:30
linux/dim: Do nothing if no time delta between samples
2023-05-30 12:44:01 +01:00
Merge android11-5.4.242+(e699d54) into msm-5.4
2023-07-26 14:21:25 +05:30
dmaengine: fix is_slave_direction() return false when DMA_DEV_TO_DEV
2024-02-23 08:25:06 +01:00
misc: eeprom: eeprom_93cx6: Add quirk for extra read clock cycle
2024-12-14 19:44:55 +01:00
ethernet: Add helper for assigning packet type when dest address does not match device address
2024-05-02 16:18:36 +02:00
eventfd: Export eventfd_ctx_do_read()
2023-09-23 10:59:40 +02:00
Merge 5.4.273 into android11-5.4-lts
2024-04-16 15:17:08 +00:00
objtool: Add support for intra-function calls
2024-04-13 12:51:29 +02:00
Merge tag 'ASB-2025-05-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2025-05-18 08:00:20 +00:00
This is the 5.4.280 stable release
2024-07-19 13:19:29 +00:00
Merge android11-5.4.274 ( 564901b) into msm-5.4
2024-07-24 20:38:43 -07:00
Revert "HID: core: store the unique system identifier in hid_device"
2023-12-11 12:08:38 +00:00
gpu: host1x: mipi: Update tegra_mipi_request() to be node based
2024-03-26 18:22:18 -04:00
Revert "hrtimers: Handle CPU state correctly on hotplug"
2025-04-26 12:28:45 +02:00
BACKPORT: FROMGIT: userfaultfd: add UFFDIO_CONTINUE ioctl
2025-05-18 08:08:42 +00:00
Drivers: hv: util: Avoid accessing a ringbuffer not initialized yet
2025-01-09 13:23:33 +01:00
i2c: Use IS_REACHABLE() for substituting empty ACPI functions
2024-09-12 11:03:50 +02:00
clockevents/drivers/i8253: Fix stop sequence for timer 0
2025-04-10 14:29:34 +02:00
Fix termination state for idr_for_each_entry_ul()
2023-11-20 10:30:15 +01:00
net: handle ARPHRD_PPP in dev_is_mac_header_xmit()
2023-09-23 10:59:55 +02:00
team: fix null-ptr-deref when team device type is changed
2023-10-10 21:46:37 +02:00
af_packet: fix vlan_get_protocol_dgram() vs MSG_PEEK
2025-01-09 13:23:35 +01:00
Revert "interconnect: Add helpers for enabling/disabling a path"
2023-08-31 13:52:19 +00:00
Merge tag 'ASB-2025-05-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2025-05-18 08:00:20 +00:00
Merge android11-5.4.281 ( d62984a) into msm-5.4
2024-10-29 01:43:17 -07:00
Merge 5.4.259 into android11-5.4-lts
2023-10-26 09:18:00 +00:00
msm: ipa: Add support for Private IP Forwarding
2024-01-31 15:08:32 +05:30
ipa_eth: Header change to pass more info from ETH to GSI
2023-06-14 09:27:04 +05:30
msm: ipa3: change variable name for indication of
2024-03-13 08:33:14 -07:00
Revert "genirq: Allow irq_chip registration functions to take a const irq_chip"
2024-08-30 10:05:12 +00:00
Revert "genirq: Allow the PM device to originate from irq domain"
2024-08-30 10:05:12 +00:00
jbd2: introduce/export functions jbd2_journal_submit|finish_inode_data_buffers()
2024-11-08 16:20:30 +01:00
Merge 5.4.287 into android11-5.4-lts
2024-12-16 10:50:16 +00:00
This is the 5.4.291 stable release
2025-03-13 14:53:52 +00:00
KVM: Explicitly verify target vCPU is online in kvm_get_vcpu()
2025-03-13 12:43:07 +01:00
leds: class: Protect brightness_show() with led_cdev->led_access mutex
2024-12-14 19:44:53 +01:00
ata: libata-sata: increase PMP SRST timeout to 10s
2023-10-10 21:46:42 +02:00
list: add "list_del_init_careful()" to go with "list_empty_careful()"
2023-06-28 10:18:35 +02:00
drm/syncobj: make lockdep complain on WAIT_FOR_SUBMIT v3
2024-03-01 13:13:38 +01:00
BACKPORT: security: add inode_init_security_anon() LSM hook
2025-02-20 04:17:45 +02:00
mcb: remove is_added flag from mcb_device struct
2023-10-25 11:53:19 +02:00
net: phy: mchp: Add support for LAN8814 QUAD PHY
2024-07-05 09:08:27 +02:00
UPSTREAM: mm: allow VM_FAULT_RETRY for multiple times
2025-05-18 08:08:42 +00:00
Merge tag 'ASB-2024-12-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2024-12-17 03:24:53 +02:00
params: lift param_set_uint_minmax to common code
2024-06-16 13:28:45 +02:00
msm: ep_pcie: Disable hot reset and ignore linkdown
2024-09-13 17:38:37 +05:30
new helper: lookup_positive_unlocked()
2023-09-23 10:59:40 +02:00
Merge tag 'ASB-2025-05-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2025-05-18 08:00:20 +00:00
Remove DECnet support from kernel
2023-06-21 15:44:10 +02:00
Remove DECnet support from kernel
2023-06-21 15:44:10 +02:00
netpoll: netpoll_send_skb() returns transmit status
2025-04-10 14:29:35 +02:00
Revert "fs/nls: make load_nls() take a const parameter"
2023-09-30 15:41:35 +00:00
Merge android11-5.4.254+ ( 91f7025) into msm-5.4
2023-10-30 22:46:41 -07:00
nvme: fixup comment for nvme RDMA Provider Type
2024-07-05 09:08:28 +02:00
mlxsw: spectrum_acl_erp: Fix object nesting warning
2024-08-19 05:33:28 +02:00
Merge android11-5.4.265+ ( a34cc1d) into msm-5.4
2024-02-29 15:10:56 +05:30
of/irq: Make of_msi_map_rid() PCI bus agnostic
2023-12-13 18:18:11 +01:00
overflow: Allow mixed type arguments
2025-03-13 12:42:52 +01:00
include/linux/pagemap.h: introduce attach/detach_page_private
2024-04-16 16:57:29 +03:00
Merge android11-5.4.281 ( d62984a) into msm-5.4
2024-10-29 01:43:17 -07:00
This is the 5.4.291 stable release
2025-03-13 14:53:52 +00:00
Merge android11-5.4.265+ ( a34cc1d) into msm-5.4
2024-02-29 15:10:56 +05:30
ANDROID: 16K: Introduce pgsize_migration_inline.h
2024-10-10 16:13:30 -07:00
ANDROID: 16K: Introduce pgsize_migration_inline.h
2024-10-10 16:13:30 -07:00
ANDROID: fix up platform_device ABI break
2023-11-28 10:15:58 +00:00
Revert "PM: domains: Fix up terminology with parent/child"
2023-06-16 09:26:26 +00:00
This is the 5.4.269 stable release
2024-02-24 15:47:08 +00:00
PM / wakeirq: support enabling wake-up irq after runtime_suspend called
2023-08-11 11:54:00 +02:00
poll_wait: add mb() to fix theoretical race between waitqueue_active() and .poll()
2025-02-01 18:18:51 +01:00
Merge 5.4.245 into android11-5.4-lts
2023-06-20 16:54:26 +00:00
pps: Fix a use-after-free
2025-03-13 12:43:19 +01:00
sched/rt: Provide migrate_disable/enable() inlines
2023-11-20 10:30:12 +01:00
Merge android11-5.4.249+ ( d57e792) into msm-5.4
2023-09-28 16:45:28 +05:30
This is the 5.4.262 stable release
2023-11-29 10:18:14 +00:00
firmware: qcom_scm: Add a call for getting dload mode
2024-06-21 10:36:14 +05:30
Merge 5.4.259 into android11-5.4-lts
2023-10-26 09:18:00 +00:00
quota: Fix slow quotaoff
2023-10-25 11:53:18 +02:00
scsi: core: raid_class: Remove raid_component_add()
2023-08-30 16:27:27 +02:00
rcu: add a helper to report consolidated flavor QS
2024-03-26 18:22:25 -04:00
Revert "regmap: allow to define reg_update_bits for no bus configuration"
2024-04-16 10:04:00 +00:00
This is the 5.4.284 stable release
2024-09-12 10:37:37 +00:00
Merge android11-5.4.242+(e699d54) into msm-5.4
2023-07-26 14:21:25 +05:30
Merge android11-5.4.259+ ( 81334f2) into msm-5.4
2023-12-18 15:40:18 +05:30
sched: Provide sched_set_fifo()
2024-04-16 16:57:36 +03:00
BACKPORT: security: add inode_init_security_anon() LSM hook
2025-02-20 04:17:45 +02:00
Revert "Revert "Revert "8250: add support for ASIX devices with a FIFO bug"""
2025-05-18 11:04:18 +03:00
serial: core: fix kernel-doc for uart_port_unlock_irqrestore()
2024-05-02 16:18:37 +02:00
BACKPORT: FROMGIT: userfaultfd/shmem: combine shmem_{mcopy_atomic,mfill_zeropage}_pte
2025-05-18 08:08:42 +00:00
Merge tag 'ASB-2025-02-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2025-02-06 22:53:05 +02:00
lib/string_helpers: Introduce string_upper() and string_lower() helpers
2023-05-30 12:44:08 +01:00
Merge android11-5.4.281 ( d62984a) into msm-5.4
2024-10-29 01:43:17 -07:00
ANDROID: preserve CRC for struct tcp_sock
2024-07-20 12:53:22 +00:00
Merge android11-5.4.274 ( 564901b) into msm-5.4
2024-07-24 20:38:43 -07:00
Revert "tracing: Constify string literal data member in struct trace_event_call"
2025-01-13 09:47:29 +00:00
u64_stats: fix u64_stats_init() for lockdep when used repeatedly in one file
2024-05-02 16:18:28 +02:00
UPSTREAM: udp: do not accept non-tunnel GSO skbs landing in a tunnel
2025-03-10 16:19:50 +00:00
units: add the HZ macros
2024-02-23 08:24:47 +01:00
Merge tag 'ASB-2025-03-05_11-5.4' into android13-5.4-lahaina
2025-04-12 09:31:28 +00:00
BACKPORT: FROMGIT: userfaultfd/shmem: modify shmem_mfill_atomic_pte to use install_pte()
2025-05-18 08:08:42 +00:00
util_macros.h: fix/rework find_closest() macros
2024-12-14 19:44:43 +01:00
vfio: Introduce interface to flush virqfd inject workqueue
2024-04-13 12:51:34 +02:00
net: do not allow gso_size to be set to GSO_BY_FRAGS
2023-08-30 16:27:17 +02:00
Merge tag 'ASB-2025-02-05_11-5.4' of https://android.googlesource.com/kernel/common into android13-5.4-lahaina
2025-02-06 22:53:05 +02:00
This is the 5.4.251 stable release
2023-08-03 10:56:28 +00:00
