diff options
| author | 2023-02-21 18:24:12 -0800 | |
|---|---|---|
| committer | 2023-02-21 18:24:12 -0800 | |
| commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
| tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/x86/entry/vdso/vdso32 | |
| download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip | |
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski:
"Core:
- Add dedicated kmem_cache for typical/small skb->head, avoid having
to access struct page at kfree time, and improve memory use.
- Introduce sysctl to set default RPS configuration for new netdevs.
- Define Netlink protocol specification format which can be used to
describe messages used by each family and auto-generate parsers.
Add tools for generating kernel data structures and uAPI headers.
- Expose all net/core sysctls inside netns.
- Remove 4s sleep in netpoll if carrier is instantly detected on
boot.
- Add configurable limit of MDB entries per port, and port-vlan.
- Continue populating drop reasons throughout the stack.
- Retire a handful of legacy Qdiscs and classifiers.
Protocols:
- Support IPv4 big TCP (TSO frames larger than 64kB).
- Add IP_LOCAL_PORT_RANGE socket option, to control local port range
on socket by socket basis.
- Track and report in procfs number of MPTCP sockets used.
- Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
manager.
- IPv6: don't check net.ipv6.route.max_size and rely on garbage
collection to free memory (similarly to IPv4).
- Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).
- ICMP: add per-rate limit counters.
- Add support for user scanning requests in ieee802154.
- Remove static WEP support.
- Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
reporting.
- WiFi 7 EHT channel puncturing support (client & AP).
BPF:
- Add a rbtree data structure following the "next-gen data structure"
precedent set by recently added linked list, that is, by using
kfunc + kptr instead of adding a new BPF map type.
- Expose XDP hints via kfuncs with initial support for RX hash and
timestamp metadata.
- Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
better support decap on GRE tunnel devices not operating in collect
metadata.
- Improve x86 JIT's codegen for PROBE_MEM runtime error checks.
- Remove the need for trace_printk_lock for bpf_trace_printk and
bpf_trace_vprintk helpers.
- Extend libbpf's bpf_tracing.h support for tracing arguments of
kprobes/uprobes and syscall as a special case.
- Significantly reduce the search time for module symbols by
livepatch and BPF.
- Enable cpumasks to be used as kptrs, which is useful for tracing
programs tracking which tasks end up running on which CPUs in
different time intervals.
- Add support for BPF trampoline on s390x and riscv64.
- Add capability to export the XDP features supported by the NIC.
- Add __bpf_kfunc tag for marking kernel functions as kfuncs.
- Add cgroup.memory=nobpf kernel parameter option to disable BPF
memory accounting for container environments.
Netfilter:
- Remove the CLUSTERIP target. It has been marked as obsolete for
years, and we still have WARN splats wrt races of the out-of-band
/proc interface installed by this target.
- Add 'destroy' commands to nf_tables. They are identical to the
existing 'delete' commands, but do not return an error if the
referenced object (set, chain, rule...) did not exist.
Driver API:
- Improve cpumask_local_spread() locality to help NICs set the right
IRQ affinity on AMD platforms.
- Separate C22 and C45 MDIO bus transactions more clearly.
- Introduce new DCB table to control DSCP rewrite on egress.
- Support configuration of Physical Layer Collision Avoidance (PLCA)
Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
shared medium Ethernet.
- Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
preemption of low priority frames by high priority frames.
- Add support for controlling MACSec offload using netlink SET.
- Rework devlink instance refcounts to allow registration and
de-registration under the instance lock. Split the code into
multiple files, drop some of the unnecessarily granular locks and
factor out common parts of netlink operation handling.
- Add TX frame aggregation parameters (for USB drivers).
- Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
messages with notifications for debug.
- Allow offloading of UDP NEW connections via act_ct.
- Add support for per action HW stats in TC.
- Support hardware miss to TC action (continue processing in SW from
a specific point in the action chain).
- Warn if old Wireless Extension user space interface is used with
modern cfg80211/mac80211 drivers. Do not support Wireless
Extensions for Wi-Fi 7 devices at all. Everyone should switch to
using nl80211 interface instead.
- Improve the CAN bit timing configuration. Use extack to return
error messages directly to user space, update the SJW handling,
including the definition of a new default value that will benefit
CAN-FD controllers, by increasing their oscillator tolerance.
New hardware / drivers:
- Ethernet:
- nVidia BlueField-3 support (control traffic driver)
- Ethernet support for imx93 SoCs
- Motorcomm yt8531 gigabit Ethernet PHY
- onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
- Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
- Amlogic gxl MDIO mux
- WiFi:
- RealTek RTL8188EU (rtl8xxxu)
- Qualcomm Wi-Fi 7 devices (ath12k)
- CAN:
- Renesas R-Car V4H
Drivers:
- Bluetooth:
- Set Per Platform Antenna Gain (PPAG) for Intel controllers.
- Ethernet NICs:
- Intel (1G, igc):
- support TSN / Qbv / packet scheduling features of i226 model
- Intel (100G, ice):
- use GNSS subsystem instead of TTY
- multi-buffer XDP support
- extend support for GPIO pins to E823 devices
- nVidia/Mellanox:
- update the shared buffer configuration on PFC commands
- implement PTP adjphase function for HW offset control
- TC support for Geneve and GRE with VF tunnel offload
- more efficient crypto key management method
- multi-port eswitch support
- Netronome/Corigine:
- add DCB IEEE support
- support IPsec offloading for NFP3800
- Freescale/NXP (enetc):
- support XDP_REDIRECT for XDP non-linear buffers
- improve reconfig, avoid link flap and waiting for idle
- support MAC Merge layer
- Other NICs:
- sfc/ef100: add basic devlink support for ef100
- ionic: rx_push mode operation (writing descriptors via MMIO)
- bnxt: use the auxiliary bus abstraction for RDMA
- r8169: disable ASPM and reset bus in case of tx timeout
- cpsw: support QSGMII mode for J721e CPSW9G
- cpts: support pulse-per-second output
- ngbe: add an mdio bus driver
- usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
- r8152: handle devices with FW with NCM support
- amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
- virtio-net: support multi buffer XDP
- virtio/vsock: replace virtio_vsock_pkt with sk_buff
- tsnep: XDP support
- Ethernet high-speed switches:
- nVidia/Mellanox (mlxsw):
- add support for latency TLV (in FW control messages)
- Microchip (sparx5):
- separate explicit and implicit traffic forwarding rules, make
the implicit rules always active
- add support for egress DSCP rewrite
- IS0 VCAP support (Ingress Classification)
- IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
etc.)
- ES2 VCAP support (Egress Access Control)
- support for Per-Stream Filtering and Policing (802.1Q,
8.6.5.1)
- Ethernet embedded switches:
- Marvell (mv88e6xxx):
- add MAB (port auth) offload support
- enable PTP receive for mv88e6390
- NXP (ocelot):
- support MAC Merge layer
- support for the the vsc7512 internal copper phys
- Microchip:
- lan9303: convert to PHYLINK
- lan966x: support TC flower filter statistics
- lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
- lan937x: support Credit Based Shaper configuration
- ksz9477: support Energy Efficient Ethernet
- other:
- qca8k: convert to regmap read/write API, use bulk operations
- rswitch: Improve TX timestamp accuracy
- Intel WiFi (iwlwifi):
- EHT (Wi-Fi 7) rate reporting
- STEP equalizer support: transfer some STEP (connection to radio
on platforms with integrated wifi) related parameters from the
BIOS to the firmware.
- Qualcomm 802.11ax WiFi (ath11k):
- IPQ5018 support
- Fine Timing Measurement (FTM) responder role support
- channel 177 support
- MediaTek WiFi (mt76):
- per-PHY LED support
- mt7996: EHT (Wi-Fi 7) support
- Wireless Ethernet Dispatch (WED) reset support
- switch to using page pool allocator
- RealTek WiFi (rtw89):
- support new version of Bluetooth co-existance
- Mobile:
- rmnet: support TX aggregation"
* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
page_pool: add a comment explaining the fragment counter usage
net: ethtool: fix __ethtool_dev_mm_supported() implementation
ethtool: pse-pd: Fix double word in comments
xsk: add linux/vmalloc.h to xsk.c
sefltests: netdevsim: wait for devlink instance after netns removal
selftest: fib_tests: Always cleanup before exit
net/mlx5e: Align IPsec ASO result memory to be as required by hardware
net/mlx5e: TC, Set CT miss to the specific ct action instance
net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
net/mlx5: Refactor tc miss handling to a single function
net/mlx5: Kconfig: Make tc offload depend on tc skb extension
net/sched: flower: Support hardware miss to tc action
net/sched: flower: Move filter handle initialization earlier
net/sched: cls_api: Support hardware miss to tc action
net/sched: Rename user cookie and act cookie
sfc: fix builds without CONFIG_RTC_LIB
sfc: clean up some inconsistent indentings
net/mlx4_en: Introduce flexible array to silence overflow warning
net: lan966x: Fix possible deadlock inside PTP
net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
...
Diffstat (limited to '')
| -rw-r--r-- | arch/x86/entry/vdso/vdso32-setup.c | 90 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/.gitignore | 2 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/fake_32bit_build.h | 25 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/note.S | 18 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/sigreturn.S | 140 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/system_call.S | 85 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/vclock_gettime.c | 4 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/vdso32.lds.S | 41 | ||||
| -rw-r--r-- | arch/x86/entry/vdso/vdso32/vgetcpu.c | 3 |
9 files changed, 408 insertions, 0 deletions
diff --git a/arch/x86/entry/vdso/vdso32-setup.c b/arch/x86/entry/vdso/vdso32-setup.c new file mode 100644 index 000000000..3b300a773 --- /dev/null +++ b/arch/x86/entry/vdso/vdso32-setup.c @@ -0,0 +1,90 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * (C) Copyright 2002 Linus Torvalds + * Portions based on the vdso-randomization code from exec-shield: + * Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar + * + * This file contains the needed initializations to support sysenter. + */ + +#include <linux/init.h> +#include <linux/smp.h> +#include <linux/kernel.h> +#include <linux/mm_types.h> +#include <linux/elf.h> + +#include <asm/processor.h> +#include <asm/vdso.h> + +#ifdef CONFIG_COMPAT_VDSO +#define VDSO_DEFAULT 0 +#else +#define VDSO_DEFAULT 1 +#endif + +/* + * Should the kernel map a VDSO page into processes and pass its + * address down to glibc upon exec()? + */ +unsigned int __read_mostly vdso32_enabled = VDSO_DEFAULT; + +static int __init vdso32_setup(char *s) +{ + vdso32_enabled = simple_strtoul(s, NULL, 0); + + if (vdso32_enabled > 1) { + pr_warn("vdso32 values other than 0 and 1 are no longer allowed; vdso disabled\n"); + vdso32_enabled = 0; + } + + return 1; +} + +/* + * For consistency, the argument vdso32=[012] affects the 32-bit vDSO + * behavior on both 64-bit and 32-bit kernels. + * On 32-bit kernels, vdso=[012] means the same thing. + */ +__setup("vdso32=", vdso32_setup); + +#ifdef CONFIG_X86_32 +__setup_param("vdso=", vdso_setup, vdso32_setup, 0); +#endif + +#ifdef CONFIG_X86_64 + +#ifdef CONFIG_SYSCTL +/* Register vsyscall32 into the ABI table */ +#include <linux/sysctl.h> + +static struct ctl_table abi_table2[] = { + { + .procname = "vsyscall32", + .data = &vdso32_enabled, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE, + }, + {} +}; + +static struct ctl_table abi_root_table2[] = { + { + .procname = "abi", + .mode = 0555, + .child = abi_table2 + }, + {} +}; + +static __init int ia32_binfmt_init(void) +{ + register_sysctl_table(abi_root_table2); + return 0; +} +__initcall(ia32_binfmt_init); +#endif /* CONFIG_SYSCTL */ + +#endif /* CONFIG_X86_64 */ diff --git a/arch/x86/entry/vdso/vdso32/.gitignore b/arch/x86/entry/vdso/vdso32/.gitignore new file mode 100644 index 000000000..516738484 --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +vdso32.lds diff --git a/arch/x86/entry/vdso/vdso32/fake_32bit_build.h b/arch/x86/entry/vdso/vdso32/fake_32bit_build.h new file mode 100644 index 000000000..db1b15f68 --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/fake_32bit_build.h @@ -0,0 +1,25 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifdef CONFIG_X86_64 + +/* + * in case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel + * configuration + */ +#undef CONFIG_64BIT +#undef CONFIG_X86_64 +#undef CONFIG_COMPAT +#undef CONFIG_PGTABLE_LEVELS +#undef CONFIG_ILLEGAL_POINTER_VALUE +#undef CONFIG_SPARSEMEM_VMEMMAP +#undef CONFIG_NR_CPUS +#undef CONFIG_PARAVIRT_XXL + +#define CONFIG_X86_32 1 +#define CONFIG_PGTABLE_LEVELS 2 +#define CONFIG_PAGE_OFFSET 0 +#define CONFIG_ILLEGAL_POINTER_VALUE 0 +#define CONFIG_NR_CPUS 1 + +#define BUILD_VDSO32_64 + +#endif diff --git a/arch/x86/entry/vdso/vdso32/note.S b/arch/x86/entry/vdso/vdso32/note.S new file mode 100644 index 000000000..2cbd39939 --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/note.S @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text. + * Here we can supply some information useful to userland. + */ + +#include <linux/build-salt.h> +#include <linux/version.h> +#include <linux/elfnote.h> + +/* Ideally this would use UTS_NAME, but using a quoted string here + doesn't work. Remember to change this when changing the + kernel's name. */ +ELFNOTE_START(Linux, 0, "a") + .long LINUX_VERSION_CODE +ELFNOTE_END + +BUILD_SALT diff --git a/arch/x86/entry/vdso/vdso32/sigreturn.S b/arch/x86/entry/vdso/vdso32/sigreturn.S new file mode 100644 index 000000000..1bd068f72 --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/sigreturn.S @@ -0,0 +1,140 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/linkage.h> +#include <asm/unistd_32.h> +#include <asm/asm-offsets.h> + +#ifndef SYSCALL_ENTER_KERNEL +#define SYSCALL_ENTER_KERNEL int $0x80 +#endif + + .text + .globl __kernel_sigreturn + .type __kernel_sigreturn,@function + nop /* this guy is needed for .LSTARTFDEDLSI1 below (watch for HACK) */ + ALIGN +__kernel_sigreturn: +.LSTART_sigreturn: + popl %eax /* XXX does this mean it needs unwind info? */ + movl $__NR_sigreturn, %eax + SYSCALL_ENTER_KERNEL +.LEND_sigreturn: +SYM_INNER_LABEL(vdso32_sigreturn_landing_pad, SYM_L_GLOBAL) + nop + .size __kernel_sigreturn,.-.LSTART_sigreturn + + .globl __kernel_rt_sigreturn + .type __kernel_rt_sigreturn,@function + ALIGN +__kernel_rt_sigreturn: +.LSTART_rt_sigreturn: + movl $__NR_rt_sigreturn, %eax + SYSCALL_ENTER_KERNEL +.LEND_rt_sigreturn: +SYM_INNER_LABEL(vdso32_rt_sigreturn_landing_pad, SYM_L_GLOBAL) + nop + .size __kernel_rt_sigreturn,.-.LSTART_rt_sigreturn + .previous + + .section .eh_frame,"a",@progbits +.LSTARTFRAMEDLSI1: + .long .LENDCIEDLSI1-.LSTARTCIEDLSI1 +.LSTARTCIEDLSI1: + .long 0 /* CIE ID */ + .byte 1 /* Version number */ + .string "zRS" /* NUL-terminated augmentation string */ + .uleb128 1 /* Code alignment factor */ + .sleb128 -4 /* Data alignment factor */ + .byte 8 /* Return address register column */ + .uleb128 1 /* Augmentation value length */ + .byte 0x1b /* DW_EH_PE_pcrel|DW_EH_PE_sdata4. */ + .byte 0 /* DW_CFA_nop */ + .align 4 +.LENDCIEDLSI1: + .long .LENDFDEDLSI1-.LSTARTFDEDLSI1 /* Length FDE */ +.LSTARTFDEDLSI1: + .long .LSTARTFDEDLSI1-.LSTARTFRAMEDLSI1 /* CIE pointer */ + /* HACK: The dwarf2 unwind routines will subtract 1 from the + return address to get an address in the middle of the + presumed call instruction. Since we didn't get here via + a call, we need to include the nop before the real start + to make up for it. */ + .long .LSTART_sigreturn-1-. /* PC-relative start address */ + .long .LEND_sigreturn-.LSTART_sigreturn+1 + .uleb128 0 /* Augmentation */ + /* What follows are the instructions for the table generation. + We record the locations of each register saved. This is + complicated by the fact that the "CFA" is always assumed to + be the value of the stack pointer in the caller. This means + that we must define the CFA of this body of code to be the + saved value of the stack pointer in the sigcontext. Which + also means that there is no fixed relation to the other + saved registers, which means that we must use DW_CFA_expression + to compute their addresses. It also means that when we + adjust the stack with the popl, we have to do it all over again. */ + +#define do_cfa_expr(offset) \ + .byte 0x0f; /* DW_CFA_def_cfa_expression */ \ + .uleb128 1f-0f; /* length */ \ +0: .byte 0x74; /* DW_OP_breg4 */ \ + .sleb128 offset; /* offset */ \ + .byte 0x06; /* DW_OP_deref */ \ +1: + +#define do_expr(regno, offset) \ + .byte 0x10; /* DW_CFA_expression */ \ + .uleb128 regno; /* regno */ \ + .uleb128 1f-0f; /* length */ \ +0: .byte 0x74; /* DW_OP_breg4 */ \ + .sleb128 offset; /* offset */ \ +1: + + do_cfa_expr(IA32_SIGCONTEXT_sp+4) + do_expr(0, IA32_SIGCONTEXT_ax+4) + do_expr(1, IA32_SIGCONTEXT_cx+4) + do_expr(2, IA32_SIGCONTEXT_dx+4) + do_expr(3, IA32_SIGCONTEXT_bx+4) + do_expr(5, IA32_SIGCONTEXT_bp+4) + do_expr(6, IA32_SIGCONTEXT_si+4) + do_expr(7, IA32_SIGCONTEXT_di+4) + do_expr(8, IA32_SIGCONTEXT_ip+4) + + .byte 0x42 /* DW_CFA_advance_loc 2 -- nop; popl eax. */ + + do_cfa_expr(IA32_SIGCONTEXT_sp) + do_expr(0, IA32_SIGCONTEXT_ax) + do_expr(1, IA32_SIGCONTEXT_cx) + do_expr(2, IA32_SIGCONTEXT_dx) + do_expr(3, IA32_SIGCONTEXT_bx) + do_expr(5, IA32_SIGCONTEXT_bp) + do_expr(6, IA32_SIGCONTEXT_si) + do_expr(7, IA32_SIGCONTEXT_di) + do_expr(8, IA32_SIGCONTEXT_ip) + + .align 4 +.LENDFDEDLSI1: + + .long .LENDFDEDLSI2-.LSTARTFDEDLSI2 /* Length FDE */ +.LSTARTFDEDLSI2: + .long .LSTARTFDEDLSI2-.LSTARTFRAMEDLSI1 /* CIE pointer */ + /* HACK: See above wrt unwind library assumptions. */ + .long .LSTART_rt_sigreturn-1-. /* PC-relative start address */ + .long .LEND_rt_sigreturn-.LSTART_rt_sigreturn+1 + .uleb128 0 /* Augmentation */ + /* What follows are the instructions for the table generation. + We record the locations of each register saved. This is + slightly less complicated than the above, since we don't + modify the stack pointer in the process. */ + + do_cfa_expr(IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_sp) + do_expr(0, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_ax) + do_expr(1, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_cx) + do_expr(2, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_dx) + do_expr(3, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_bx) + do_expr(5, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_bp) + do_expr(6, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_si) + do_expr(7, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_di) + do_expr(8, IA32_RT_SIGFRAME_sigcontext-4 + IA32_SIGCONTEXT_ip) + + .align 4 +.LENDFDEDLSI2: + .previous diff --git a/arch/x86/entry/vdso/vdso32/system_call.S b/arch/x86/entry/vdso/vdso32/system_call.S new file mode 100644 index 000000000..d33c6513f --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/system_call.S @@ -0,0 +1,85 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * AT_SYSINFO entry point +*/ + +#include <linux/linkage.h> +#include <asm/dwarf2.h> +#include <asm/cpufeatures.h> +#include <asm/alternative.h> + + .text + .globl __kernel_vsyscall + .type __kernel_vsyscall,@function + ALIGN +__kernel_vsyscall: + CFI_STARTPROC + /* + * Reshuffle regs so that all of any of the entry instructions + * will preserve enough state. + * + * A really nice entry sequence would be: + * pushl %edx + * pushl %ecx + * movl %esp, %ecx + * + * Unfortunately, naughty Android versions between July and December + * 2015 actually hardcode the traditional Linux SYSENTER entry + * sequence. That is severely broken for a number of reasons (ask + * anyone with an AMD CPU, for example). Nonetheless, we try to keep + * it working approximately as well as it ever worked. + * + * This link may elucidate some of the history: + * https://android-review.googlesource.com/#/q/Iac3295376d61ef83e713ac9b528f3b50aa780cd7 + * personally, I find it hard to understand what's going on there. + * + * Note to future user developers: DO NOT USE SYSENTER IN YOUR CODE. + * Execute an indirect call to the address in the AT_SYSINFO auxv + * entry. That is the ONLY correct way to make a fast 32-bit system + * call on Linux. (Open-coding int $0x80 is also fine, but it's + * slow.) + */ + pushl %ecx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ecx, 0 + pushl %edx + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET edx, 0 + pushl %ebp + CFI_ADJUST_CFA_OFFSET 4 + CFI_REL_OFFSET ebp, 0 + + #define SYSENTER_SEQUENCE "movl %esp, %ebp; sysenter" + #define SYSCALL_SEQUENCE "movl %ecx, %ebp; syscall" + +#ifdef CONFIG_X86_64 + /* If SYSENTER (Intel) or SYSCALL32 (AMD) is available, use it. */ + ALTERNATIVE_2 "", SYSENTER_SEQUENCE, X86_FEATURE_SYSENTER32, \ + SYSCALL_SEQUENCE, X86_FEATURE_SYSCALL32 +#else + ALTERNATIVE "", SYSENTER_SEQUENCE, X86_FEATURE_SEP +#endif + + /* Enter using int $0x80 */ + int $0x80 +SYM_INNER_LABEL(int80_landing_pad, SYM_L_GLOBAL) + + /* + * Restore EDX and ECX in case they were clobbered. EBP is not + * clobbered (the kernel restores it), but it's cleaner and + * probably faster to pop it than to adjust ESP using addl. + */ + popl %ebp + CFI_RESTORE ebp + CFI_ADJUST_CFA_OFFSET -4 + popl %edx + CFI_RESTORE edx + CFI_ADJUST_CFA_OFFSET -4 + popl %ecx + CFI_RESTORE ecx + CFI_ADJUST_CFA_OFFSET -4 + RET + CFI_ENDPROC + + .size __kernel_vsyscall,.-__kernel_vsyscall + .previous diff --git a/arch/x86/entry/vdso/vdso32/vclock_gettime.c b/arch/x86/entry/vdso/vdso32/vclock_gettime.c new file mode 100644 index 000000000..86981decf --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/vclock_gettime.c @@ -0,0 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0 +#define BUILD_VDSO32 +#include "fake_32bit_build.h" +#include "../vclock_gettime.c" diff --git a/arch/x86/entry/vdso/vdso32/vdso32.lds.S b/arch/x86/entry/vdso/vdso32/vdso32.lds.S new file mode 100644 index 000000000..8a3be0700 --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/vdso32.lds.S @@ -0,0 +1,41 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Linker script for 32-bit vDSO. + * We #include the file to define the layout details. + * + * This file defines the version script giving the user-exported symbols in + * the DSO. + */ + +#include <asm/page.h> + +#define BUILD_VDSO32 + +#include "../vdso-layout.lds.S" + +/* The ELF entry point can be used to set the AT_SYSINFO value. */ +ENTRY(__kernel_vsyscall); + +/* + * This controls what userland symbols we export from the vDSO. + */ +VERSION +{ + LINUX_2.6 { + global: + __vdso_clock_gettime; + __vdso_gettimeofday; + __vdso_time; + __vdso_clock_getres; + __vdso_clock_gettime64; + __vdso_getcpu; + }; + + LINUX_2.5 { + global: + __kernel_vsyscall; + __kernel_sigreturn; + __kernel_rt_sigreturn; + local: *; + }; +} diff --git a/arch/x86/entry/vdso/vdso32/vgetcpu.c b/arch/x86/entry/vdso/vdso32/vgetcpu.c new file mode 100644 index 000000000..3a9791f5e --- /dev/null +++ b/arch/x86/entry/vdso/vdso32/vgetcpu.c @@ -0,0 +1,3 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "fake_32bit_build.h" +#include "../vgetcpu.c" |
