From a5f7a5bb3b7f28ba7e4fa246775b29a0e5537255 Mon Sep 17 00:00:00 2001 From: Jinke Han Date: Tue, 8 Sep 2026 15:37:42 +0800 Subject: x86/kprobes: Fix crash when probing CS CALL instructions When using eBPF to probe CS CALL instructions within a function, a crash can be triggered. The eBPF tool probes offset 257 of the __hrtimer_run_queues() function: <__hrtimer_run_queues+249>: nopl 0x0(%rax,%rax,1) <__hrtimer_run_queues+254>: mov %r14,%rdi <__hrtimer_run_queues+257>: cs call <__x86_indirect_thunk_r12> <__hrtimer_run_queues+263>: mov %eax,%r12d <__hrtimer_run_queues+266>: xchg %ax,%ax <__hrtimer_run_queues+268>: mov %r13,%rdi Which triggers this crash: BUG: unable to handle page fault for address: 00000000000f41c9 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP NOPTI CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P RIP: 0010:__hrtimer_run_queues+0x106/0x230 Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is at the 6th byte of the above CS CALL instruction. Since the CS CALL instruction occupies 6 bytes, the exception occurred in the middle of that call instruction. The root cause is that when using eBPF tools to probe in the middle of a function, a kprobe with INT3 is used as the underlying implementation. During single-step emulation of the original CALL instruction, int3_emulate_call() assumes that the probed CALL instruction is 5 bytes long. However, the actual CS-prefixed CALL instruction occupies 6 bytes, so it constructs an incorrect exception return address. When the CPU returns from the kprobe handler, the next instruction to be executed is at the address of the last byte of that CS CALL instruction. Coincidentally, starting from that address, the CPU fetches and decodes a completely different instruction, which ultimately triggers a kernel crash. Fix the issue by using the actual instruction length obtained from the instruction decoder when constructing the exception return address, rather than relying on the hardcoded CALL_INSN_SIZE macro. [ mingo: Refined the changelog ] Fixes: 6256e668b7af ("x86/kprobes: Use int3 instead of debug trap for single-step") Suggested-by: Masami Hiramatsu (Google) Signed-off-by: Jinke Han Signed-off-by: Ingo Molnar Reviewed-by: Masami Hiramatsu (Google) Acked-by: Yafang Shao Acked-by: Borislav Petkov Cc: Peter Zijlstra Link: https://patch.msgid.link/20260908073742.GA10517@didi-ThinkCentre-M920t-N000 --- .../bindings/ipmi/aspeed,ast2400-ibt-bmc.yaml | 44 +++++++++ .../bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml | 109 +++++++++++++++++++++ .../devicetree/bindings/ipmi/ipmb-dev.yaml | 56 +++++++++++ .../devicetree/bindings/ipmi/ipmi-ipmb.yaml | 67 +++++++++++++ .../devicetree/bindings/ipmi/ipmi-smic.yaml | 63 ++++++++++++ .../bindings/ipmi/nuvoton,npcm750-kcs-bmc.yaml | 55 +++++++++++ .../devicetree/bindings/ipmi/ssif-bmc.yaml | 38 +++++++ 7 files changed, 432 insertions(+) create mode 100644 Documentation/devicetree/bindings/ipmi/aspeed,ast2400-ibt-bmc.yaml create mode 100644 Documentation/devicetree/bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml create mode 100644 Documentation/devicetree/bindings/ipmi/ipmb-dev.yaml create mode 100644 Documentation/devicetree/bindings/ipmi/ipmi-ipmb.yaml create mode 100644 Documentation/devicetree/bindings/ipmi/ipmi-smic.yaml create mode 100644 Documentation/devicetree/bindings/ipmi/nuvoton,npcm750-kcs-bmc.yaml create mode 100644 Documentation/devicetree/bindings/ipmi/ssif-bmc.yaml (limited to 'Documentation/devicetree/bindings/ipmi') diff --git a/Documentation/devicetree/bindings/ipmi/aspeed,ast2400-ibt-bmc.yaml b/Documentation/devicetree/bindings/ipmi/aspeed,ast2400-ibt-bmc.yaml new file mode 100644 index 000000000..c4f7cdbbe --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/aspeed,ast2400-ibt-bmc.yaml @@ -0,0 +1,44 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/aspeed,ast2400-ibt-bmc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Aspeed Block Transfer (BT) IPMI interface + +maintainers: + - Joel Stanley + +properties: + compatible: + enum: + - aspeed,ast2400-ibt-bmc + - aspeed,ast2500-ibt-bmc + - aspeed,ast2600-ibt-bmc + + reg: + maxItems: 1 + + clocks: + maxItems: 1 + + interrupts: + maxItems: 1 + +required: + - compatible + - reg + - clocks + +additionalProperties: false + +examples: + - | + #include + + bt@1e789140 { + compatible = "aspeed,ast2400-ibt-bmc"; + reg = <0x1e789140 0x18>; + interrupts = <8>; + clocks = <&syscon ASPEED_CLK_GATE_LCLK>; + }; diff --git a/Documentation/devicetree/bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml b/Documentation/devicetree/bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml new file mode 100644 index 000000000..610c79863 --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/aspeed,ast2400-kcs-bmc.yaml @@ -0,0 +1,109 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/aspeed,ast2400-kcs-bmc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: ASPEED BMC KCS Devices + +maintainers: + - Andrew Jeffery + +description: | + The Aspeed BMC SoCs typically use the Keyboard-Controller-Style (KCS) + interfaces on the LPC bus for in-band IPMI communication with their host. + +properties: + compatible: + oneOf: + - description: Channel ID derived from reg + items: + enum: + - aspeed,ast2400-kcs-bmc-v2 + - aspeed,ast2500-kcs-bmc-v2 + - aspeed,ast2600-kcs-bmc + + - description: Old-style with explicit channel ID, no reg + deprecated: true + items: + enum: + - aspeed,ast2400-kcs-bmc + - aspeed,ast2500-kcs-bmc + + interrupts: + maxItems: 1 + + reg: + # maxItems: 3 + items: + - description: IDR register + - description: ODR register + - description: STR register + + clocks: + maxItems: 1 + + aspeed,lpc-io-reg: + $ref: /schemas/types.yaml#/definitions/uint32-array + minItems: 1 + maxItems: 2 + description: | + The host CPU LPC IO data and status addresses for the device. For most + channels the status address is derived from the data address, but the + status address may be optionally provided. + + aspeed,lpc-interrupts: + $ref: /schemas/types.yaml#/definitions/uint32-array + minItems: 2 + maxItems: 2 + description: | + A 2-cell property expressing the LPC SerIRQ number and the interrupt + level/sense encoding (specified in the standard fashion). + + Note that the generated interrupt is issued from the BMC to the host, and + thus the target interrupt controller is not captured by the BMC's + devicetree. + + kcs_chan: + deprecated: true + $ref: /schemas/types.yaml#/definitions/uint32 + description: The LPC channel number in the controller + + kcs_addr: + deprecated: true + $ref: /schemas/types.yaml#/definitions/uint32 + description: The host CPU IO map address + +required: + - compatible + - interrupts + +additionalProperties: false + +allOf: + - if: + properties: + compatible: + contains: + enum: + - aspeed,ast2400-kcs-bmc + - aspeed,ast2500-kcs-bmc + then: + required: + - kcs_chan + - kcs_addr + else: + required: + - reg + - aspeed,lpc-io-reg + +examples: + - | + #include + kcs3: kcs@24 { + compatible = "aspeed,ast2600-kcs-bmc"; + reg = <0x24 0x1>, <0x30 0x1>, <0x3c 0x1>; + aspeed,lpc-io-reg = <0xca2>; + aspeed,lpc-interrupts = <11 IRQ_TYPE_LEVEL_LOW>; + interrupts = <8>; + }; diff --git a/Documentation/devicetree/bindings/ipmi/ipmb-dev.yaml b/Documentation/devicetree/bindings/ipmi/ipmb-dev.yaml new file mode 100644 index 000000000..8b0d71901 --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/ipmb-dev.yaml @@ -0,0 +1,56 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/ipmb-dev.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: The Intelligent Platform Management Bus(IPMB) Device + +description: | + The IPMB is an I2C bus which provides interconnection between a Baseboard + Management Controller(BMC) and chassis electronics. The BMC sends IPMI + requests to intelligent controllers like Satellite Management Controller(MC) + devices via IPMB and the device sends responses back to the BMC. + This device uses an I2C slave device to send and receive IPMB messages, + either on a BMC or other MC. A miscellaneous device provices a user space + program to communicate with the kernel and the backend device. Some IPMB + devices only support the I2C protocol and not the SMB protocol. + + IPMB communications protocol Specification V1.0 + https://www.intel.com/content/dam/www/public/us/en/documents/product-briefs/ipmp-spec-v1.0.pdf + +maintainers: + - Ninad Palsule + +properties: + compatible: + enum: + - ipmb-dev + + reg: + maxItems: 1 + + i2c-protocol: + description: + Use I2C block transfer instead of SMBUS block transfer. + type: boolean + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + #include + i2c { + #address-cells = <1>; + #size-cells = <0>; + + ipmb-dev@10 { + compatible = "ipmb-dev"; + reg = <(0x10 | I2C_OWN_SLAVE_ADDRESS)>; + i2c-protocol; + }; + }; diff --git a/Documentation/devicetree/bindings/ipmi/ipmi-ipmb.yaml b/Documentation/devicetree/bindings/ipmi/ipmi-ipmb.yaml new file mode 100644 index 000000000..52647bff3 --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/ipmi-ipmb.yaml @@ -0,0 +1,67 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/ipmi-ipmb.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: IPMI IPMB device + +description: IPMI IPMB device bindings + +maintainers: + - Corey Minyard + +properties: + compatible: + enum: + - ipmi-ipmb + + device_type: + items: + - const: ipmi + + reg: + maxItems: 1 + + bmcaddr: + $ref: /schemas/types.yaml#/definitions/uint8 + description: The address of the BMC on the IPMB bus. Defaults to 0x20. + + retry-time: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Time between retries of sends, in milliseconds. Defaults to 250. + + max-retries: + $ref: /schemas/types.yaml#/definitions/uint32 + description: Number of retries before a failure is declared. Defaults to 1. + + slave-dev: + $ref: /schemas/types.yaml#/definitions/phandle + description: | + The slave i2c device. If not present, the main device is used. This + lets you use two devices on the IPMB, one for master and one for slave, + in case you have a slave device that can only be a slave. The slave + will receive messages and the master will transmit. + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + i2c { + #address-cells = <1>; + #size-cells = <0>; + + ipmi-ipmb@40 { + compatible = "ipmi-ipmb"; + device_type = "ipmi"; + reg = <0x40>; + bmcaddr = /bits/ 8 <0x20>; + retry-time = <250>; + max-retries = <1>; + }; + }; diff --git a/Documentation/devicetree/bindings/ipmi/ipmi-smic.yaml b/Documentation/devicetree/bindings/ipmi/ipmi-smic.yaml new file mode 100644 index 000000000..4bffa3d86 --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/ipmi-smic.yaml @@ -0,0 +1,63 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/ipmi-smic.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: IPMI device + +description: IPMI device bindings + +maintainers: + - Corey Minyard + +properties: + compatible: + enum: + - ipmi-kcs + - ipmi-smic + - ipmi-bt + + device_type: + items: + - const: ipmi + + reg: + maxItems: 1 + + interrupts: + description: Interface is polled if this property is omitted. + maxItems: 1 + + reg-size: + description: The access width of the register in bytes. Defaults to 1. + $ref: /schemas/types.yaml#/definitions/uint32 + enum: [1, 2, 4, 8] + + reg-spacing: + $ref: /schemas/types.yaml#/definitions/uint32 + description: The number of bytes between register starts. Defaults to 1. + + reg-shift: + description: | + The amount of bits to shift the register content to the right to get + the data into bit zero. + $ref: /schemas/types.yaml#/definitions/uint32 + maximum: 56 + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + smic@fff3a000 { + compatible = "ipmi-smic"; + device_type = "ipmi"; + reg = <0xfff3a000 0x1000>; + interrupts = <0 24 4>; + reg-size = <4>; + reg-spacing = <4>; + }; diff --git a/Documentation/devicetree/bindings/ipmi/nuvoton,npcm750-kcs-bmc.yaml b/Documentation/devicetree/bindings/ipmi/nuvoton,npcm750-kcs-bmc.yaml new file mode 100644 index 000000000..fc5df1c5e --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/nuvoton,npcm750-kcs-bmc.yaml @@ -0,0 +1,55 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/nuvoton,npcm750-kcs-bmc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Nuvoton NPCM KCS BMC + +maintainers: + - Avi Fishman + - Tomer Maimon + - Tali Perry + +description: + The Nuvoton SOCs (NPCM) are commonly used as BMCs (Baseboard Management + Controllers) and the KCS interface can be used to perform in-band IPMI + communication with their host. + +properties: + compatible: + oneOf: + - const: nuvoton,npcm750-kcs-bmc + - items: + - enum: + - nuvoton,npcm845-kcs-bmc + - const: nuvoton,npcm750-kcs-bmc + + reg: + maxItems: 1 + + interrupts: + maxItems: 1 + + kcs_chan: + description: The KCS channel number in the controller + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 1 + maximum: 3 + +required: + - compatible + - reg + - interrupts + - kcs_chan + +additionalProperties: false + +examples: + - | + kcs@0 { + compatible = "nuvoton,npcm750-kcs-bmc"; + reg = <0x0 0x40>; + interrupts = <9 4>; + kcs_chan = <1>; + }; diff --git a/Documentation/devicetree/bindings/ipmi/ssif-bmc.yaml b/Documentation/devicetree/bindings/ipmi/ssif-bmc.yaml new file mode 100644 index 000000000..02b662d78 --- /dev/null +++ b/Documentation/devicetree/bindings/ipmi/ssif-bmc.yaml @@ -0,0 +1,38 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/ipmi/ssif-bmc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: SSIF IPMI BMC interface + +description: SSIF IPMI BMC device bindings + +maintainers: + - Quan Nguyen + +properties: + compatible: + enum: + - ssif-bmc + + reg: + maxItems: 1 + +required: + - compatible + - reg + +additionalProperties: false + +examples: + - | + i2c { + #address-cells = <1>; + #size-cells = <0>; + + ssif-bmc@10 { + compatible = "ssif-bmc"; + reg = <0x10>; + }; + }; -- cgit v1.3.1