Commit Graph

21 Commits

Author SHA1 Message Date
tao zeng
4d6ae43593 mm: optimize thread stack usage on arm64 [1/1]
PD#SWPL-1219

Problem:
On arm64, thread stack is 16KB for each task. If running task number
is large, this type of memory may over 40MB. It's a large amount on
small memory platform. But most case thread only use less 4KB stack.
It's waste of memory and we need optimize it.

Solution:
1. Pre-allocate a vmalloc address space for task stack;
2. Only map 1st page for stack and handle page fault in EL1
   when stack growth triggered exception;
3. handle stack switch for exception.

Verify:
p212

Change-Id: I47f511ccfa2868d982bc10a820ed6435b6d52ba9
Signed-off-by: tao zeng <tao.zeng@amlogic.com>
2018-12-17 14:52:05 +08:00
Greg Kroah-Hartman
9797dcb8c7 Merge 4.9.104 into android-4.9
Changes in 4.9.104
	MIPS: c-r4k: Fix data corruption related to cache coherence
	MIPS: ptrace: Expose FIR register through FP regset
	MIPS: Fix ptrace(2) PTRACE_PEEKUSR and PTRACE_POKEUSR accesses to o32 FGRs
	KVM: Fix spelling mistake: "cop_unsuable" -> "cop_unusable"
	affs_lookup(): close a race with affs_remove_link()
	aio: fix io_destroy(2) vs. lookup_ioctx() race
	ALSA: timer: Fix pause event notification
	do d_instantiate/unlock_new_inode combinations safely
	mmc: sdhci-iproc: remove hard coded mmc cap 1.8v
	mmc: sdhci-iproc: fix 32bit writes for TRANSFER_MODE register
	libata: Blacklist some Sandisk SSDs for NCQ
	libata: blacklist Micron 500IT SSD with MU01 firmware
	xen-swiotlb: fix the check condition for xen_swiotlb_free_coherent
	drm/vmwgfx: Fix 32-bit VMW_PORT_HB_[IN|OUT] macros
	IB/hfi1: Use after free race condition in send context error path
	Revert "ipc/shm: Fix shmat mmap nil-page protection"
	ipc/shm: fix shmat() nil address after round-down when remapping
	kasan: fix memory hotplug during boot
	kernel/sys.c: fix potential Spectre v1 issue
	kernel/signal.c: avoid undefined behaviour in kill_something_info
	KVM/VMX: Expose SSBD properly to guests
	KVM: s390: vsie: fix < 8k check for the itdba
	KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
	kvm: x86: IA32_ARCH_CAPABILITIES is always supported
	firewire-ohci: work around oversized DMA reads on JMicron controllers
	x86/tsc: Allow TSC calibration without PIT
	NFSv4: always set NFS_LOCK_LOST when a lock is lost.
	ALSA: hda - Use IS_REACHABLE() for dependency on input
	kvm: x86: fix KVM_XEN_HVM_CONFIG ioctl
	netfilter: ipv6: nf_defrag: Pass on packets to stack per RFC2460
	tracing/hrtimer: Fix tracing bugs by taking all clock bases and modes into account
	PCI: Add function 1 DMA alias quirk for Marvell 9128
	Input: psmouse - fix Synaptics detection when protocol is disabled
	i40iw: Zero-out consumer key on allocate stag for FMR
	tools lib traceevent: Simplify pointer print logic and fix %pF
	perf callchain: Fix attr.sample_max_stack setting
	tools lib traceevent: Fix get_field_str() for dynamic strings
	perf record: Fix failed memory allocation for get_cpuid_str
	iommu/vt-d: Use domain instead of cache fetching
	dm thin: fix documentation relative to low water mark threshold
	net: stmmac: dwmac-meson8b: fix setting the RGMII TX clock on Meson8b
	net: stmmac: dwmac-meson8b: propagate rate changes to the parent clock
	nfs: Do not convert nfs_idmap_cache_timeout to jiffies
	watchdog: sp5100_tco: Fix watchdog disable bit
	kconfig: Don't leak main menus during parsing
	kconfig: Fix automatic menu creation mem leak
	kconfig: Fix expr_free() E_NOT leak
	mac80211_hwsim: fix possible memory leak in hwsim_new_radio_nl()
	ipmi/powernv: Fix error return code in ipmi_powernv_probe()
	Btrfs: set plug for fsync
	btrfs: Fix out of bounds access in btrfs_search_slot
	Btrfs: fix scrub to repair raid6 corruption
	btrfs: fail mount when sb flag is not in BTRFS_SUPER_FLAG_SUPP
	HID: roccat: prevent an out of bounds read in kovaplus_profile_activated()
	fm10k: fix "failed to kill vid" message for VF
	device property: Define type of PROPERTY_ENRTY_*() macros
	jffs2: Fix use-after-free bug in jffs2_iget()'s error handling path
	powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
	powerpc/numa: Ensure nodes initialized for hotplug
	RDMA/mlx5: Avoid memory leak in case of XRCD dealloc failure
	ntb_transport: Fix bug with max_mw_size parameter
	gianfar: prevent integer wrapping in the rx handler
	tcp_nv: fix potential integer overflow in tcpnv_acked
	kvm: Map PFN-type memory regions as writable (if possible)
	ocfs2: return -EROFS to mount.ocfs2 if inode block is invalid
	ocfs2/acl: use 'ip_xattr_sem' to protect getting extended attribute
	ocfs2: return error when we attempt to access a dirty bh in jbd2
	mm/mempolicy: fix the check of nodemask from user
	mm/mempolicy: add nodes_empty check in SYSC_migrate_pages
	asm-generic: provide generic_pmdp_establish()
	sparc64: update pmdp_invalidate() to return old pmd value
	mm: thp: use down_read_trylock() in khugepaged to avoid long block
	mm: pin address_space before dereferencing it while isolating an LRU page
	mm/fadvise: discard partial page if endbyte is also EOF
	openvswitch: Remove padding from packet before L3+ conntrack processing
	IB/ipoib: Fix for potential no-carrier state
	drm/nouveau/pmu/fuc: don't use movw directly anymore
	netfilter: ipv6: nf_defrag: Kill frag queue on RFC2460 failure
	x86/power: Fix swsusp_arch_resume prototype
	firmware: dmi_scan: Fix handling of empty DMI strings
	ACPI: processor_perflib: Do not send _PPC change notification if not ready
	ACPI / scan: Use acpi_bus_get_status() to initialize ACPI_TYPE_DEVICE devs
	bpf: fix selftests/bpf test_kmod.sh failure when CONFIG_BPF_JIT_ALWAYS_ON=y
	MIPS: generic: Fix machine compatible matching
	MIPS: TXx9: use IS_BUILTIN() for CONFIG_LEDS_CLASS
	xen-netfront: Fix race between device setup and open
	xen/grant-table: Use put_page instead of free_page
	RDS: IB: Fix null pointer issue
	arm64: spinlock: Fix theoretical trylock() A-B-A with LSE atomics
	proc: fix /proc/*/map_files lookup
	cifs: silence compiler warnings showing up with gcc-8.0.0
	bcache: properly set task state in bch_writeback_thread()
	bcache: fix for allocator and register thread race
	bcache: fix for data collapse after re-attaching an attached device
	bcache: return attach error when no cache set exist
	tools/libbpf: handle issues with bpf ELF objects containing .eh_frames
	bpf: fix rlimit in reuseport net selftest
	vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
	locking/qspinlock: Ensure node->count is updated before initialising node
	irqchip/gic-v3: Ignore disabled ITS nodes
	cpumask: Make for_each_cpu_wrap() available on UP as well
	irqchip/gic-v3: Change pr_debug message to pr_devel
	ARC: Fix malformed ARC_EMUL_UNALIGNED default
	ptr_ring: prevent integer overflow when calculating size
	libata: Fix compile warning with ATA_DEBUG enabled
	selftests: pstore: Adding config fragment CONFIG_PSTORE_RAM=m
	selftests: memfd: add config fragment for fuse
	ARM: OMAP2+: timer: fix a kmemleak caused in omap_get_timer_dt
	ARM: OMAP3: Fix prm wake interrupt for resume
	ARM: OMAP1: clock: Fix debugfs_create_*() usage
	ibmvnic: Free RX socket buffer in case of adapter error
	iwlwifi: mvm: fix security bug in PN checking
	iwlwifi: mvm: always init rs with 20mhz bandwidth rates
	NFC: llcp: Limit size of SDP URI
	rxrpc: Work around usercopy check
	mac80211: round IEEE80211_TX_STATUS_HEADROOM up to multiple of 4
	mac80211: fix a possible leak of station stats
	mac80211: fix calling sleeping function in atomic context
	mac80211: Do not disconnect on invalid operating class
	md raid10: fix NULL deference in handle_write_completed()
	drm/exynos: g2d: use monotonic timestamps
	drm/exynos: fix comparison to bitshift when dealing with a mask
	locking/xchg/alpha: Add unconditional memory barrier to cmpxchg()
	md: raid5: avoid string overflow warning
	kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
	powerpc/bpf/jit: Fix 32-bit JIT for seccomp_data access
	s390/cio: fix ccw_device_start_timeout API
	s390/cio: fix return code after missing interrupt
	s390/cio: clear timer when terminating driver I/O
	PKCS#7: fix direct verification of SignerInfo signature
	ARM: OMAP: Fix dmtimer init for omap1
	smsc75xx: fix smsc75xx_set_features()
	regulatory: add NUL to request alpha2
	integrity/security: fix digsig.c build error with header file
	locking/xchg/alpha: Fix xchg() and cmpxchg() memory ordering bugs
	x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
	mac80211: drop frames with unexpected DS bits from fast-rx to slow path
	arm64: fix unwind_frame() for filtered out fn for function graph tracing
	macvlan: fix use-after-free in macvlan_common_newlink()
	kvm: fix warning for CONFIG_HAVE_KVM_EVENTFD builds
	fs: dcache: Avoid livelock between d_alloc_parallel and __d_add
	fs: dcache: Use READ_ONCE when accessing i_dir_seq
	md: fix a potential deadlock of raid5/raid10 reshape
	md/raid1: fix NULL pointer dereference
	batman-adv: fix packet checksum in receive path
	batman-adv: invalidate checksum on fragment reassembly
	netfilter: ebtables: convert BUG_ONs to WARN_ONs
	batman-adv: Ignore invalid batadv_iv_gw during netlink send
	batman-adv: Ignore invalid batadv_v_gw during netlink send
	batman-adv: Fix netlink dumping of BLA claims
	batman-adv: Fix netlink dumping of BLA backbones
	nvme-pci: Fix nvme queue cleanup if IRQ setup fails
	clocksource/drivers/fsl_ftm_timer: Fix error return checking
	ceph: fix dentry leak when failing to init debugfs
	ARM: orion5x: Revert commit 4904dbda41.
	qrtr: add MODULE_ALIAS macro to smd
	r8152: fix tx packets accounting
	virtio-gpu: fix ioctl and expose the fixed status to userspace.
	dmaengine: rcar-dmac: fix max_chunk_size for R-Car Gen3
	bcache: fix kcrashes with fio in RAID5 backend dev
	ip6_tunnel: fix IFLA_MTU ignored on NEWLINK
	sit: fix IFLA_MTU ignored on NEWLINK
	ARM: dts: NSP: Fix amount of RAM on BCM958625HR
	powerpc/boot: Fix random libfdt related build errors
	gianfar: Fix Rx byte accounting for ndev stats
	net/tcp/illinois: replace broken algorithm reference link
	nvmet: fix PSDT field check in command format
	xen/pirq: fix error path cleanup when binding MSIs
	drm/sun4i: Fix dclk_set_phase
	Btrfs: send, fix issuing write op when processing hole in no data mode
	selftests/powerpc: Skip the subpage_prot tests if the syscall is unavailable
	KVM: PPC: Book3S HV: Fix VRMA initialization with 2MB or 1GB memory backing
	iwlwifi: mvm: fix TX of CCMP 256
	watchdog: f71808e_wdt: Fix magic close handling
	watchdog: sbsa: use 32-bit read for WCV
	batman-adv: Fix multicast packet loss with a single WANT_ALL_IPV4/6 flag
	e1000e: Fix check_for_link return value with autoneg off
	e1000e: allocate ring descriptors with dma_zalloc_coherent
	ia64/err-inject: Use get_user_pages_fast()
	RDMA/qedr: Fix kernel panic when running fio over NFSoRDMA
	RDMA/qedr: Fix iWARP write and send with immediate
	IB/mlx4: Fix corruption of RoCEv2 IPv4 GIDs
	IB/mlx4: Include GID type when deleting GIDs from HW table under RoCE
	IB/mlx5: Fix an error code in __mlx5_ib_modify_qp()
	fbdev: Fixing arbitrary kernel leak in case FBIOGETCMAP_SPARC in sbusfb_ioctl_helper().
	fsl/fman: avoid sleeping in atomic context while adding an address
	net: qcom/emac: Use proper free methods during TX
	net: smsc911x: Fix unload crash when link is up
	IB/core: Fix possible crash to access NULL netdev
	xen: xenbus: use put_device() instead of kfree()
	arm64: Relax ARM_SMCCC_ARCH_WORKAROUND_1 discovery
	dmaengine: mv_xor_v2: Fix clock resource by adding a register clock
	netfilter: ebtables: fix erroneous reject of last rule
	bnxt_en: Check valid VNIC ID in bnxt_hwrm_vnic_set_tpa().
	workqueue: use put_device() instead of kfree()
	ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmtu
	sunvnet: does not support GSO for sctp
	drm/imx: move arming of the vblank event to atomic_flush
	net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off
	batman-adv: fix header size check in batadv_dbg_arp()
	batman-adv: Fix skbuff rcsum on packet reroute
	vti4: Don't count header length twice on tunnel setup
	vti4: Don't override MTU passed on link creation via IFLA_MTU
	perf/cgroup: Fix child event counting bug
	brcmfmac: Fix check for ISO3166 code
	kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
	RDMA/ucma: Correct option size check using optlen
	RDMA/qedr: fix QP's ack timeout configuration
	RDMA/qedr: Fix rc initialization on CNQ allocation failure
	mm/mempolicy.c: avoid use uninitialized preferred_node
	mm, thp: do not cause memcg oom for thp
	selftests: ftrace: Add probe event argument syntax testcase
	selftests: ftrace: Add a testcase for string type with kprobe_event
	selftests: ftrace: Add a testcase for probepoint
	batman-adv: fix multicast-via-unicast transmission with AP isolation
	batman-adv: fix packet loss for broadcasted DHCP packets to a server
	ARM: 8748/1: mm: Define vdso_start, vdso_end as array
	net: qmi_wwan: add BroadMobi BM806U 2020:2033
	perf/x86/intel: Fix linear IP of PEBS real_ip on Haswell and later CPUs
	llc: properly handle dev_queue_xmit() return value
	builddeb: Fix header package regarding dtc source links
	mm/kmemleak.c: wait for scan completion before disabling free
	net: Fix untag for vlan packets without ethernet header
	net: mvneta: fix enable of all initialized RXQs
	sh: fix debug trap failure to process signals before return to user
	nvme: don't send keep-alives to the discovery controller
	x86/pgtable: Don't set huge PUD/PMD on non-leaf entries
	x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init
	fs/proc/proc_sysctl.c: fix potential page fault while unregistering sysctl table
	swap: divide-by-zero when zero length swap file on ssd
	sr: get/drop reference to device in revalidate and check_events
	Force log to disk before reading the AGF during a fstrim
	cpufreq: CPPC: Initialize shared perf capabilities of CPUs
	dp83640: Ensure against premature access to PHY registers after reset
	mm/ksm: fix interaction with THP
	mm: fix races between address_space dereference and free in page_evicatable
	Btrfs: bail out on error during replay_dir_deletes
	Btrfs: fix NULL pointer dereference in log_dir_items
	btrfs: Fix possible softlock on single core machines
	ocfs2/dlm: don't handle migrate lockres if already in shutdown
	sched/rt: Fix rq->clock_update_flags < RQCF_ACT_SKIP warning
	KVM: VMX: raise internal error for exception during invalid protected mode state
	fscache: Fix hanging wait on page discarded by writeback
	sparc64: Make atomic_xchg() an inline function rather than a macro.
	net: bgmac: Fix endian access in bgmac_dma_tx_ring_free()
	btrfs: tests/qgroup: Fix wrong tree backref level
	Btrfs: fix copy_items() return value when logging an inode
	btrfs: fix lockdep splat in btrfs_alloc_subvolume_writers
	rxrpc: Fix Tx ring annotation after initial Tx failure
	rxrpc: Don't treat call aborts as conn aborts
	xen/acpi: off by one in read_acpi_id()
	drivers: macintosh: rack-meter: really fix bogus memsets
	ACPI: acpi_pad: Fix memory leak in power saving threads
	powerpc/mpic: Check if cpu_possible() in mpic_physmask()
	m68k: set dma and coherent masks for platform FEC ethernets
	parisc/pci: Switch LBA PCI bus from Hard Fail to Soft Fail mode
	hwmon: (nct6775) Fix writing pwmX_mode
	powerpc/perf: Prevent kernel address leak to userspace via BHRB buffer
	powerpc/perf: Fix kernel address leak via sampling registers
	tools/thermal: tmon: fix for segfault
	selftests: Print the test we're running to /dev/kmsg
	net/mlx5: Protect from command bit overflow
	ath10k: Fix kernel panic while using worker (ath10k_sta_rc_update_wk)
	cxgb4: Setup FW queues before registering netdev
	ima: Fallback to the builtin hash algorithm
	virtio-net: Fix operstate for virtio when no VIRTIO_NET_F_STATUS
	arm: dts: socfpga: fix GIC PPI warning
	cpufreq: cppc_cpufreq: Fix cppc_cpufreq_init() failure path
	zorro: Set up z->dev.dma_mask for the DMA API
	bcache: quit dc->writeback_thread when BCACHE_DEV_DETACHING is set
	ACPICA: Events: add a return on failure from acpi_hw_register_read
	ACPICA: acpi: acpica: fix acpi operand cache leak in nseval.c
	cxgb4: Fix queue free path of ULD drivers
	i2c: mv64xxx: Apply errata delay only in standard mode
	KVM: lapic: stop advertising DIRECTED_EOI when in-kernel IOAPIC is in use
	perf top: Fix top.call-graph config option reading
	perf stat: Fix core dump when flag T is used
	IB/core: Honor port_num while resolving GID for IB link layer
	regulator: gpio: Fix some error handling paths in 'gpio_regulator_probe()'
	spi: bcm-qspi: fIX some error handling paths
	MIPS: ath79: Fix AR724X_PLL_REG_PCIE_CONFIG offset
	PCI: Restore config space on runtime resume despite being unbound
	ipmi_ssif: Fix kernel panic at msg_done_handler
	powerpc: Add missing prototype for arch_irq_work_raise()
	f2fs: fix to check extent cache in f2fs_drop_extent_tree
	perf/core: Fix perf_output_read_group()
	drm/panel: simple: Fix the bus format for the Ontat panel
	hwmon: (pmbus/max8688) Accept negative page register values
	hwmon: (pmbus/adm1275) Accept negative page register values
	perf/x86/intel: Properly save/restore the PMU state in the NMI handler
	cdrom: do not call check_disk_change() inside cdrom_open()
	perf/x86/intel: Fix large period handling on Broadwell CPUs
	perf/x86/intel: Fix event update for auto-reload
	arm64: dts: qcom: Fix SPI5 config on MSM8996
	soc: qcom: wcnss_ctrl: Fix increment in NV upload
	gfs2: Fix fallocate chunk size
	x86/devicetree: Initialize device tree before using it
	x86/devicetree: Fix device IRQ settings in DT
	ALSA: vmaster: Propagate slave error
	dmaengine: pl330: fix a race condition in case of threaded irqs
	dmaengine: rcar-dmac: Check the done lists in rcar_dmac_chan_get_residue()
	enic: enable rq before updating rq descriptors
	hwrng: stm32 - add reset during probe
	dmaengine: qcom: bam_dma: get num-channels and num-ees from dt
	net: stmmac: ensure that the device has released ownership before reading data
	net: stmmac: ensure that the MSS desc is the last desc to set the own bit
	cpufreq: Reorder cpufreq_online() error code path
	PCI: Add function 1 DMA alias quirk for Marvell 88SE9220
	udf: Provide saner default for invalid uid / gid
	ARM: dts: bcm283x: Fix probing of bcm2835-i2s
	audit: return on memory error to avoid null pointer dereference
	rcu: Call touch_nmi_watchdog() while printing stall warnings
	pinctrl: sh-pfc: r8a7796: Fix MOD_SEL register pin assignment for SSI pins group
	MIPS: Octeon: Fix logging messages with spurious periods after newlines
	drm/rockchip: Respect page offset for PRIME mmap calls
	x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified
	perf tests: Use arch__compare_symbol_names to compare symbols
	perf report: Fix memory corruption in --branch-history mode --branch-history
	selftests/net: fixes psock_fanout eBPF test case
	netlabel: If PF_INET6, check sk_buff ip header version
	regmap: Correct comparison in regmap_cached
	ARM: dts: imx7d: cl-som-imx7: fix pinctrl_enet
	ARM: dts: porter: Fix HDMI output routing
	regulator: of: Add a missing 'of_node_put()' in an error handling path of 'of_regulator_match()'
	pinctrl: msm: Use dynamic GPIO numbering
	kdb: make "mdr" command repeat
	Linux 4.9.104

Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
2018-05-30 13:19:56 +02:00
Pratyush Anand
c3655e72f8 arm64: fix unwind_frame() for filtered out fn for function graph tracing
[ Upstream commit 9f416319f4 ]

do_task_stat() calls get_wchan(), which further does unwind_frame().
unwind_frame() restores frame->pc to original value in case function
graph tracer has modified a return address (LR) in a stack frame to hook
a function return. However, if function graph tracer has hit a filtered
function, then we can't unwind it as ftrace_push_return_trace() has
biased the index(frame->graph) with a 'huge negative'
offset(-FTRACE_NOTRACE_DEPTH).

Moreover, arm64 stack walker defines index(frame->graph) as unsigned
int, which can not compare a -ve number.

Similar problem we can have with calling of walk_stackframe() from
save_stack_trace_tsk() or dump_backtrace().

This patch fixes unwind_frame() to test the index for -ve value and
restore index accordingly before we can restore frame->pc.

Reproducer:

cd /sys/kernel/debug/tracing/
echo schedule > set_graph_notrace
echo 1 > options/display-graph
echo wakeup > current_tracer
ps -ef | grep -i agent

Above commands result in:
Unable to handle kernel paging request at virtual address ffff801bd3d1e000
pgd = ffff8003cbe97c00
[ffff801bd3d1e000] *pgd=0000000000000000, *pud=0000000000000000
Internal error: Oops: 96000006 [#1] SMP
[...]
CPU: 5 PID: 11696 Comm: ps Not tainted 4.11.0+ #33
[...]
task: ffff8003c21ba000 task.stack: ffff8003cc6c0000
PC is at unwind_frame+0x12c/0x180
LR is at get_wchan+0xd4/0x134
pc : [<ffff00000808892c>] lr : [<ffff0000080860b8>] pstate: 60000145
sp : ffff8003cc6c3ab0
x29: ffff8003cc6c3ab0 x28: 0000000000000001
x27: 0000000000000026 x26: 0000000000000026
x25: 00000000000012d8 x24: 0000000000000000
x23: ffff8003c1c04000 x22: ffff000008c83000
x21: ffff8003c1c00000 x20: 000000000000000f
x19: ffff8003c1bc0000 x18: 0000fffffc593690
x17: 0000000000000000 x16: 0000000000000001
x15: 0000b855670e2b60 x14: 0003e97f22cf1d0f
x13: 0000000000000001 x12: 0000000000000000
x11: 00000000e8f4883e x10: 0000000154f47ec8
x9 : 0000000070f367c0 x8 : 0000000000000000
x7 : 00008003f7290000 x6 : 0000000000000018
x5 : 0000000000000000 x4 : ffff8003c1c03cb0
x3 : ffff8003c1c03ca0 x2 : 00000017ffe80000
x1 : ffff8003cc6c3af8 x0 : ffff8003d3e9e000

Process ps (pid: 11696, stack limit = 0xffff8003cc6c0000)
Stack: (0xffff8003cc6c3ab0 to 0xffff8003cc6c4000)
[...]
[<ffff00000808892c>] unwind_frame+0x12c/0x180
[<ffff000008305008>] do_task_stat+0x864/0x870
[<ffff000008305c44>] proc_tgid_stat+0x3c/0x48
[<ffff0000082fde0c>] proc_single_show+0x5c/0xb8
[<ffff0000082b27e0>] seq_read+0x160/0x414
[<ffff000008289e6c>] __vfs_read+0x58/0x164
[<ffff00000828b164>] vfs_read+0x88/0x144
[<ffff00000828c2e8>] SyS_read+0x60/0xc0
[<ffff0000080834a0>] __sys_trace_return+0x0/0x4

Fixes: 20380bb390 (arm64: ftrace: fix a stack tracer's output under function graph tracer)
Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
[catalin.marinas@arm.com: replace WARN_ON with WARN_ON_ONCE]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:50:30 +02:00
Mark Rutland
0c7aad6502 UPSTREAM: arm64: prep stack walkers for THREAD_INFO_IN_TASK
When CONFIG_THREAD_INFO_IN_TASK is selected, task stacks may be freed
before a task is destroyed. To account for this, the stacks are
refcounted, and when manipulating the stack of another task, it is
necessary to get/put the stack to ensure it isn't freed and/or re-used
while we do so.

This patch reworks the arm64 stack walking code to account for this.
When CONFIG_THREAD_INFO_IN_TASK is not selected these perform no
refcounting, and this should only be a structural change that does not
affect behaviour.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 9bbd4c56b0)

Change-Id: I3ca86d1284456eeabe862bec8271570cc7e4a720
Signed-off-by: Greg Hackmann <ghackmann@google.com>
2018-04-24 13:28:13 -07:00
Mark Rutland
abcc8cc3e4 UPSTREAM: arm64: unexport walk_stackframe
The walk_stackframe functions is architecture-specific, with a varying
prototype, and common code should not use it directly. None of its
current users can be built as modules. With THREAD_INFO_IN_TASK, users
will also need to hold a stack reference before calling it.

There's no reason for it to be exported, and it's very easy to misuse,
so unexport it for now.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 2020a5ae7c)

Change-Id: If09c303ccd98dcc030e20a16a2eab5bf7bb54e4a
Signed-off-by: Greg Hackmann <ghackmann@google.com>
2018-04-24 13:28:13 -07:00
Mark Rutland
ab96e216b6 UPSTREAM: arm64: factor out current_stack_pointer
We define current_stack_pointer in <asm/thread_info.h>, though other
files and header relying upon it do not have this necessary include, and
are thus fragile to changes in the header soup.

Subsequent patches will affect the header soup such that directly
including <asm/thread_info.h> may result in a circular header include in
some of these cases, so we can't simply include <asm/thread_info.h>.

Instead, factor current_thread_info into its own header, and have all
existing users include this explicitly.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit a9ea0017eb)

Change-Id: I3b509f998c13da8f614ecd39052ed803009ab8a1
Signed-off-by: Greg Hackmann <ghackmann@google.com>
2018-04-24 13:28:12 -07:00
Mark Rutland
b5e7307d9d arm64: fix dump_backtrace/unwind_frame with NULL tsk
In some places, dump_backtrace() is called with a NULL tsk parameter,
e.g. in bug_handler() in arch/arm64, or indirectly via show_stack() in
core code. The expectation is that this is treated as if current were
passed instead of NULL. Similar is true of unwind_frame().

Commit a80a0eb70c ("arm64: make irq_stack_ptr more robust") didn't
take this into account. In dump_backtrace() it compares tsk against
current *before* we check if tsk is NULL, and in unwind_frame() we never
set tsk if it is NULL.

Due to this, we won't initialise irq_stack_ptr in either function. In
dump_backtrace() this results in calling dump_mem() for memory
immediately above the IRQ stack range, rather than for the relevant
range on the task stack. In unwind_frame we'll reject unwinding frames
on the IRQ stack.

In either case this results in incomplete or misleading backtrace
information, but is not otherwise problematic. The initial percpu areas
(including the IRQ stacks) are allocated in the linear map, and dump_mem
uses __get_user(), so we shouldn't access anything with side-effects,
and will handle holes safely.

This patch fixes the issue by having both functions handle the NULL tsk
case before doing anything else with tsk.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Fixes: a80a0eb70c ("arm64: make irq_stack_ptr more robust")
Acked-by: James Morse <james.morse@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-26 14:24:01 +01:00
Pratyush Anand
98ab10e977 arm64: ftrace: add save_stack_trace_regs()
Currently, enabling stacktrace of a kprobe events generates warning:

  echo stacktrace > /sys/kernel/debug/tracing/trace_options
  echo "p xhci_irq" > /sys/kernel/debug/tracing/kprobe_events
  echo 1 > /sys/kernel/debug/tracing/events/kprobes/enable

save_stack_trace_regs() not implemented yet.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 0 at ../kernel/stacktrace.c:74 save_stack_trace_regs+0x3c/0x48
Modules linked in:

CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.8.0-rc4-dirty #5128
Hardware name: ARM Juno development board (r1) (DT)
task: ffff800975dd1900 task.stack: ffff800975ddc000
PC is at save_stack_trace_regs+0x3c/0x48
LR is at save_stack_trace_regs+0x3c/0x48
pc : [<ffff000008126c64>] lr : [<ffff000008126c64>] pstate: 600003c5
sp : ffff80097ef52c00

Call trace:
   save_stack_trace_regs+0x3c/0x48
   __ftrace_trace_stack+0x168/0x208
   trace_buffer_unlock_commit_regs+0x5c/0x7c
   kprobe_trace_func+0x308/0x3d8
   kprobe_dispatcher+0x58/0x60
   kprobe_breakpoint_handler+0xbc/0x18c
   brk_handler+0x50/0x90
   do_debug_exception+0x50/0xbc

This patch implements save_stack_trace_regs(), so that stacktrace of a
kprobe events can be obtained.

After this patch, there is no warning and we can see the stacktrace for
kprobe events in trace buffer.

more /sys/kernel/debug/tracing/trace
          <idle>-0     [004] d.h.  1356.000496: p_xhci_irq_0:(xhci_irq+0x0/0x9ac)
          <idle>-0     [004] d.h.  1356.000497: <stack trace>
  => xhci_irq
  => __handle_irq_event_percpu
  => handle_irq_event_percpu
  => handle_irq_event
  => handle_fasteoi_irq
  => generic_handle_irq
  => __handle_domain_irq
  => gic_handle_irq
  => el1_irq
  => arch_cpu_idle
  => default_idle_call
  => cpu_startup_entry
  => secondary_start_kernel
  =>

Tested-by: David A. Long <dave.long@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Signed-off-by: Pratyush Anand <panand@redhat.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-05 13:41:52 +01:00
Yang Shi
a80a0eb70c arm64: make irq_stack_ptr more robust
Switching between stacks is only valid if we are tracing ourselves while on the
irq_stack, so it is only valid when in current and non-preemptible context,
otherwise is is just zeroed off.

Fixes: 132cd887b5 ("arm64: Modify stack trace and dump for use with irq_stack")
Acked-by: James Morse <james.morse@arm.com>
Tested-by: James Morse <james.morse@arm.com>
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-12 15:53:51 +00:00
Yang Shi
bcaf669b4b arm64: disable kasan when accessing frame->fp in unwind_frame
When boot arm64 kernel with KASAN enabled, the below error is reported by
kasan:

BUG: KASAN: out-of-bounds in unwind_frame+0xec/0x260 at addr ffffffc064d57ba0
Read of size 8 by task pidof/499
page:ffffffbdc39355c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x0()
page dumped because: kasan: bad access detected
CPU: 2 PID: 499 Comm: pidof Not tainted 4.5.0-rc1 #119
Hardware name: Freescale Layerscape 2085a RDB Board (DT)
Call trace:
[<ffffffc00008d078>] dump_backtrace+0x0/0x290
[<ffffffc00008d32c>] show_stack+0x24/0x30
[<ffffffc0006a981c>] dump_stack+0x8c/0xd8
[<ffffffc0002e4400>] kasan_report_error+0x558/0x588
[<ffffffc0002e4958>] kasan_report+0x60/0x70
[<ffffffc0002e3188>] __asan_load8+0x60/0x78
[<ffffffc00008c92c>] unwind_frame+0xec/0x260
[<ffffffc000087e60>] get_wchan+0x110/0x160
[<ffffffc0003b647c>] do_task_stat+0xb44/0xb68
[<ffffffc0003b7730>] proc_tgid_stat+0x40/0x50
[<ffffffc0003ac840>] proc_single_show+0x88/0xd8
[<ffffffc000345be8>] seq_read+0x370/0x770
[<ffffffc00030aba0>] __vfs_read+0xc8/0x1d8
[<ffffffc00030c0ec>] vfs_read+0x94/0x168
[<ffffffc00030d458>] SyS_read+0xb8/0x128
[<ffffffc000086530>] el0_svc_naked+0x24/0x28
Memory state around the buggy address:
 ffffffc064d57a80: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 f4 f4
 ffffffc064d57b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffc064d57b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
                                  ^
 ffffffc064d57c00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffc064d57c80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Since the shadow byte pointed by the report is 0, so it may mean it is just hit
oob in non-current task. So, disable the instrumentation to silence these
warnings.

Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Yang Shi <yang.shi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-09 17:55:30 +00:00
AKASHI Takahiro
20380bb390 arm64: ftrace: fix a stack tracer's output under function graph tracer
Function graph tracer modifies a return address (LR) in a stack frame
to hook a function return. This will result in many useless entries
(return_to_handler) showing up in
 a) a stack tracer's output
 b) perf call graph (with perf record -g)
 c) dump_backtrace (at panic et al.)

For example, in case of a),
  $ echo function_graph > /sys/kernel/debug/tracing/current_tracer
  $ echo 1 > /proc/sys/kernel/stack_trace_enabled
  $ cat /sys/kernel/debug/tracing/stack_trace
        Depth    Size   Location    (54 entries)
        -----    ----   --------
  0)     4504      16   gic_raise_softirq+0x28/0x150
  1)     4488      80   smp_cross_call+0x38/0xb8
  2)     4408      48   return_to_handler+0x0/0x40
  3)     4360      32   return_to_handler+0x0/0x40
  ...

In case of b),
  $ echo function_graph > /sys/kernel/debug/tracing/current_tracer
  $ perf record -e mem:XXX:x -ag -- sleep 10
  $ perf report
                  ...
                  |          |          |--0.22%-- 0x550f8
                  |          |          |          0x10888
                  |          |          |          el0_svc_naked
                  |          |          |          sys_openat
                  |          |          |          return_to_handler
                  |          |          |          return_to_handler
                  ...

In case of c),
  $ echo function_graph > /sys/kernel/debug/tracing/current_tracer
  $ echo c > /proc/sysrq-trigger
  ...
  Call trace:
  [<ffffffc00044d3ac>] sysrq_handle_crash+0x24/0x30
  [<ffffffc000092250>] return_to_handler+0x0/0x40
  [<ffffffc000092250>] return_to_handler+0x0/0x40
  ...

This patch replaces such entries with real addresses preserved in
current->ret_stack[] at unwind_frame(). This way, we can cover all
the cases.

Reviewed-by: Jungseok Lee <jungseoklee85@gmail.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
[will: fixed minor context changes conflicting with irq stack bits]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-21 17:26:02 +00:00
AKASHI Takahiro
fe13f95b72 arm64: pass a task parameter to unwind_frame()
Function graph tracer modifies a return address (LR) in a stack frame
to hook a function's return. This will result in many useless entries
(return_to_handler) showing up in a call stack list.
We will fix this problem in a later patch ("arm64: ftrace: fix a stack
tracer's output under function graph tracer"). But since real return
addresses are saved in ret_stack[] array in struct task_struct,
unwind functions need to be notified of, in addition to a stack pointer
address, which task is being traced in order to find out real return
addresses.

This patch extends unwind functions' interfaces by adding an extra
argument of a pointer to task_struct.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-21 17:26:01 +00:00
James Morse
971c67ce37 arm64: reduce stack use in irq_handler
The code for switching to irq_stack stores three pieces of information on
the stack, fp+lr, as a fake stack frame (that lets us walk back onto the
interrupted tasks stack frame), and the address of the struct pt_regs that
contains the register values from kernel entry. (which dump_backtrace()
will print in any stack trace).

To reduce this, we store fp, and the pointer to the struct pt_regs.
unwind_frame() can recognise this as the irq_stack dummy frame, (as it only
appears at the top of the irq_stack), and use the struct pt_regs values
to find the missing interrupted link-register.

Suggested-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-15 17:09:08 +00:00
James Morse
1ffe199b1c arm64: when walking onto the task stack, check sp & fp are in current->stack
When unwind_frame() reaches the bottom of the irq_stack, the last fp
points to the original task stack. unwind_frame() uses
IRQ_STACK_TO_TASK_STACK() to find the sp value. If either values is
wrong, we may end up walking a corrupt stack.

Check these values are sane by testing if they are both on the stack
pointed to by current->stack.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-10 12:08:09 +00:00
AKASHI Takahiro
132cd887b5 arm64: Modify stack trace and dump for use with irq_stack
This patch allows unwind_frame() to traverse from interrupt stack to task
stack correctly. It requires data from a dummy stack frame, created
during irq_stack_entry(), added by a later patch.

A similar approach is taken to modify dump_backtrace(), which expects to
find struct pt_regs underneath any call to functions marked __exception.
When on an irq_stack, the struct pt_regs is stored on the old task stack,
the location of which is stored in the dummy stack frame.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
[james.morse: merged two patches, reworked for per_cpu irq_stacks, and
 no alignment guarantees, added irq_stack definitions]
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-12-08 11:41:51 +00:00
Will Deacon
9702970c7b Revert "ARM64: unwind: Fix PC calculation"
This reverts commit e306dfd06f.

With this patch applied, we were the only architecture making this sort
of adjustment to the PC calculation in the unwinder. This causes
problems for ftrace, where the PC values are matched against the
contents of the stack frames in the callchain and fail to match any
records after the address adjustment.

Whilst there has been some effort to change ftrace to workaround this,
those patches are not yet ready for mainline and, since we're the odd
architecture in this regard, let's just step in line with other
architectures (like arch/arm/) for now.

Cc: <stable@vger.kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-10-28 17:07:07 +00:00
Behan Webster
bb28cec4ea arm64: LLVMLinux: Use current_stack_pointer in save_stack_trace_tsk
Use the global current_stack_pointer to get the value of the stack pointer.
This change supports being able to compile the kernel with both gcc and clang.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Signed-off-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Reviewed-by: Olof Johansson <olof@lixom.net>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-09-08 14:39:19 +01:00
AKASHI Takahiro
26e2ae3999 arm64: Add 'notrace' attribute to unwind_frame() for ftrace
walk_stackframe() calls unwind_frame(), and if walk_stackframe() is
"notrace", unwind_frame() should be also "notrace".

Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-05-29 09:04:31 +01:00
Olof Johansson
e306dfd06f ARM64: unwind: Fix PC calculation
The frame PC value in the unwind code used to just take the saved LR
value and use that.  That's incorrect as a stack trace, since it shows
the return path stack, not the call path stack.

In particular, it shows faulty information in case the bl is done as
the very last instruction of one label, since the return point will be
in the next label. That can easily be seen with tail calls to panic(),
which is marked __noreturn and thus doesn't have anything useful after it.

Easiest here is to just correct the unwind code and do a -4, to get the
actual call site for the backtrace instead of the return site.

Signed-off-by: Olof Johansson <olof@lixom.net>
Cc: stable@vger.kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-02-17 09:16:33 +00:00
Konstantin Khlebnikov
26920dd2da ARM64: fix framepointer check in unwind_frame
We need at least 24 bytes above frame pointer.

Signed-off-by: Konstantin Khlebnikov <k.khlebnikov@samsung.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2013-12-19 17:43:10 +00:00
Catalin Marinas
60ffc30d56 arm64: Exception handling
The patch contains the exception entry code (kernel/entry.S), pt_regs
structure and related accessors, undefined instruction trapping and
stack tracing.

AArch64 Linux kernel (including kernel threads) runs in EL1 mode using
the SP1 stack. The vectors don't have a fixed address, only alignment
(2^11) requirements.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Acked-by: Olof Johansson <olof@lixom.net>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
2012-09-17 10:24:46 +01:00