From 23ed2be5404da7cee6a519fa69bf22d0f69da4e4 Mon Sep 17 00:00:00 2001 From: Haibo Chen Date: Wed, 26 Jul 2023 19:24:57 +0800 Subject: arm64: dts: imx93: add the Flex-CAN stop mode by GPR MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit imx93 A0 chip use the internal q-channel handshake signal in LPCG and CCM to automatically handle the Flex-CAN stop mode. But this method meet issue when do the system PM stress test. IC can't fix it easily. So in the new imx93 A1 chip, IC drop this method, and involve back the old way，use the GPR method to trigger the Flex-CAN stop mode signal. Now NXP claim to drop imx93 A0, and only support imx93 A1. So here add the stop mode through GPR. This patch also fix a typo for aonmix_ns_gpr. Signed-off-by: Haibo Chen Link: https://lore.kernel.org/all/20230726112458.3524165-1-haibo.chen@nxp.com Signed-off-by: Marc Kleine-Budde --- arch/arm64/boot/dts/freescale/imx93.dtsi | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch') diff --git a/arch/arm64/boot/dts/freescale/imx93.dtsi b/arch/arm64/boot/dts/freescale/imx93.dtsi index 6f85a05ee7e1..dcf6e4846ac9 100644 --- a/arch/arm64/boot/dts/freescale/imx93.dtsi +++ b/arch/arm64/boot/dts/freescale/imx93.dtsi @@ -185,7 +185,7 @@ #size-cells = <1>; ranges; - anomix_ns_gpr: syscon@44210000 { + aonmix_ns_gpr: syscon@44210000 { compatible = "fsl,imx93-aonmix-ns-syscfg", "syscon"; reg = <0x44210000 0x1000>; }; @@ -319,6 +319,7 @@ assigned-clock-parents = <&clk IMX93_CLK_SYS_PLL_PFD1_DIV2>; assigned-clock-rates = <40000000>; fsl,clk-source = /bits/ 8 <0>; + fsl,stop-mode = <&aonmix_ns_gpr 0x14 0>; status = "disabled"; }; @@ -591,6 +592,7 @@ assigned-clock-parents = <&clk IMX93_CLK_SYS_PLL_PFD1_DIV2>; assigned-clock-rates = <40000000>; fsl,clk-source = /bits/ 8 <0>; + fsl,stop-mode = <&wakeupmix_gpr 0x0c 2>; status = "disabled"; }; -- cgit From 2f1b0d3d733169eb11680bfa97c266ae5e757148 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Wed, 4 Oct 2023 14:07:05 +0200 Subject: riscv, bpf: Sign-extend return values MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The RISC-V architecture does not expose sub-registers, and hold all 32-bit values in a sign-extended format [1] [2]: | The compiler and calling convention maintain an invariant that all | 32-bit values are held in a sign-extended format in 64-bit | registers. Even 32-bit unsigned integers extend bit 31 into bits | 63 through 32. Consequently, conversion between unsigned and | signed 32-bit integers is a no-op, as is conversion from a signed | 32-bit integer to a signed 64-bit integer. While BPF, on the other hand, exposes sub-registers, and use zero-extension (similar to arm64/x86). This has led to some subtle bugs, where a BPF JITted program has not sign-extended the a0 register (return value in RISC-V land), passed the return value up the kernel, e.g.: | int from_bpf(void); | | long foo(void) | { | return from_bpf(); | } Here, a0 would be 0xffff_ffff, instead of the expected 0xffff_ffff_ffff_ffff. Internally, the RISC-V JIT uses a5 as a dedicated register for BPF return values. Keep a5 zero-extended, but explicitly sign-extend a0 (which is used outside BPF land). Now that a0 (RISC-V ABI) and a5 (BPF ABI) differs, a0 is only moved to a5 for non-BPF native calls (BPF_PSEUDO_CALL). Fixes: 2353ecc6f91f ("bpf, riscv: add BPF JIT for RV64G") Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann Link: https://github.com/riscv/riscv-isa-manual/releases/download/riscv-isa-release-056b6ff-2023-10-02/unpriv-isa-asciidoc.pdf # [2] Link: https://github.com/riscv-non-isa/riscv-elf-psabi-doc/releases/download/draft-20230929-e5c800e661a53efe3c2678d71a306323b60eb13b/riscv-abi.pdf # [2] Link: https://lore.kernel.org/bpf/20231004120706.52848-2-bjorn@kernel.org --- arch/riscv/net/bpf_jit_comp64.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index ecd3ae6f4116..de4c9957d223 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -245,7 +245,7 @@ static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx) emit_addi(RV_REG_SP, RV_REG_SP, stack_adjust, ctx); /* Set return value. */ if (!is_tail_call) - emit_mv(RV_REG_A0, RV_REG_A5, ctx); + emit_addiw(RV_REG_A0, RV_REG_A5, 0, ctx); emit_jalr(RV_REG_ZERO, is_tail_call ? RV_REG_T3 : RV_REG_RA, is_tail_call ? (RV_FENTRY_NINSNS + 1) * 4 : 0, /* skip reserved nops and TCC init */ ctx); @@ -1515,7 +1515,8 @@ out_be: if (ret) return ret; - emit_mv(bpf_to_rv_reg(BPF_REG_0, ctx), RV_REG_A0, ctx); + if (insn->src_reg != BPF_PSEUDO_CALL) + emit_mv(bpf_to_rv_reg(BPF_REG_0, ctx), RV_REG_A0, ctx); break; } /* tail call */ -- cgit From 7112cd26e606c7ba51f9cc5c1905f06039f6f379 Mon Sep 17 00:00:00 2001 From: Björn Töpel Date: Wed, 4 Oct 2023 14:07:06 +0200 Subject: riscv, bpf: Track both a0 (RISC-V ABI) and a5 (BPF) return values MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The RISC-V BPF uses a5 for BPF return values, which are zero-extended, whereas the RISC-V ABI uses a0 which is sign-extended. In other words, a5 and a0 can differ, and are used in different context. The BPF trampoline are used for both BPF programs, and regular kernel functions. Make sure that the RISC-V BPF trampoline saves, and restores both a0 and a5. Fixes: 49b5e77ae3e2 ("riscv, bpf: Add bpf trampoline support for RV64") Signed-off-by: Björn Töpel Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20231004120706.52848-3-bjorn@kernel.org --- arch/riscv/net/bpf_jit_comp64.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'arch') diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c index de4c9957d223..8581693e62d3 100644 --- a/arch/riscv/net/bpf_jit_comp64.c +++ b/arch/riscv/net/bpf_jit_comp64.c @@ -759,8 +759,10 @@ static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_of if (ret) return ret; - if (save_ret) - emit_sd(RV_REG_FP, -retval_off, regmap[BPF_REG_0], ctx); + if (save_ret) { + emit_sd(RV_REG_FP, -retval_off, RV_REG_A0, ctx); + emit_sd(RV_REG_FP, -(retval_off - 8), regmap[BPF_REG_0], ctx); + } /* update branch with beqz */ if (ctx->insns) { @@ -853,7 +855,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET); if (save_ret) { - stack_size += 8; + stack_size += 16; /* Save both A5 (BPF R0) and A0 */ retval_off = stack_size; } @@ -957,6 +959,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, if (ret) goto out; emit_sd(RV_REG_FP, -retval_off, RV_REG_A0, ctx); + emit_sd(RV_REG_FP, -(retval_off - 8), regmap[BPF_REG_0], ctx); im->ip_after_call = ctx->insns + ctx->ninsns; /* 2 nops reserved for auipc+jalr pair */ emit(rv_nop(), ctx); @@ -988,8 +991,10 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, if (flags & BPF_TRAMP_F_RESTORE_REGS) restore_args(nregs, args_off, ctx); - if (save_ret) + if (save_ret) { emit_ld(RV_REG_A0, -retval_off, RV_REG_FP, ctx); + emit_ld(regmap[BPF_REG_0], -(retval_off - 8), RV_REG_FP, ctx); + } emit_ld(RV_REG_S1, -sreg_off, RV_REG_FP, ctx); -- cgit From ce10fc0604bc6a0d626ed8e5d69088057edc71ab Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Tue, 10 Oct 2023 22:20:09 +0200 Subject: s390/bpf: Fix clobbering the caller's backchain in the trampoline One of the first things that s390x kernel functions do is storing the the caller's frame address (backchain) on stack. This makes unwinding possible. The backchain is always stored at frame offset 152, which is inside the 160-byte stack area, that the functions allocate for their callees. The callees must preserve the backchain; the remaining 152 bytes they may use as they please. Currently the trampoline uses all 160 bytes, clobbering the backchain. This causes kernel panics when using __builtin_return_address() in functions called by the trampoline. Fix by reducing the usage of the caller-reserved stack area by 8 bytes in the trampoline. Fixes: 528eb2cb87bc ("s390/bpf: Implement arch_prepare_bpf_trampoline()") Reported-by: Song Liu Signed-off-by: Ilya Leoshkevich Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20231010203512.385819-2-iii@linux.ibm.com --- arch/s390/net/bpf_jit_comp.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'arch') diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 2861e3360aff..9a9733e4bc80 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -2260,8 +2260,12 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, tjit->run_ctx_off = alloc_stack(tjit, sizeof(struct bpf_tramp_run_ctx)); tjit->tccnt_off = alloc_stack(tjit, sizeof(u64)); - /* The caller has already reserved STACK_FRAME_OVERHEAD bytes. */ - tjit->stack_size -= STACK_FRAME_OVERHEAD; + /* + * In accordance with the s390x ABI, the caller has allocated + * STACK_FRAME_OVERHEAD bytes for us. 8 of them contain the caller's + * backchain, and the rest we can use. + */ + tjit->stack_size -= STACK_FRAME_OVERHEAD - sizeof(u64); tjit->orig_stack_args_off = tjit->stack_size + STACK_FRAME_OVERHEAD; /* aghi %r15,-stack_size */ -- cgit From 5356ba1ff4f2417e1aebcf99aab35c1ea94dd6d7 Mon Sep 17 00:00:00 2001 From: Ilya Leoshkevich Date: Tue, 10 Oct 2023 22:20:10 +0200 Subject: s390/bpf: Fix unwinding past the trampoline When functions called by the trampoline panic, the backtrace that is printed stops at the trampoline, because the trampoline does not store its caller's frame address (backchain) on stack; it also stores the return address at a wrong location. Store both the same way as is already done for the regular eBPF programs. Fixes: 528eb2cb87bc ("s390/bpf: Implement arch_prepare_bpf_trampoline()") Signed-off-by: Ilya Leoshkevich Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/20231010203512.385819-3-iii@linux.ibm.com --- arch/s390/net/bpf_jit_comp.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) (limited to 'arch') diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 9a9733e4bc80..e507692e51e7 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -2066,6 +2066,7 @@ struct bpf_tramp_jit { * func_addr's original caller */ int stack_size; /* Trampoline stack size */ + int backchain_off; /* Offset of backchain */ int stack_args_off; /* Offset of stack arguments for calling * func_addr, has to be at the top */ @@ -2086,9 +2087,10 @@ struct bpf_tramp_jit { * for __bpf_prog_enter() return value and * func_addr respectively */ - int r14_off; /* Offset of saved %r14 */ int run_ctx_off; /* Offset of struct bpf_tramp_run_ctx */ int tccnt_off; /* Offset of saved tailcall counter */ + int r14_off; /* Offset of saved %r14, has to be at the + * bottom */ int do_fexit; /* do_fexit: label */ }; @@ -2247,8 +2249,12 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, * Calculate the stack layout. */ - /* Reserve STACK_FRAME_OVERHEAD bytes for the callees. */ + /* + * Allocate STACK_FRAME_OVERHEAD bytes for the callees. As the s390x + * ABI requires, put our backchain at the end of the allocated memory. + */ tjit->stack_size = STACK_FRAME_OVERHEAD; + tjit->backchain_off = tjit->stack_size - sizeof(u64); tjit->stack_args_off = alloc_stack(tjit, nr_stack_args * sizeof(u64)); tjit->reg_args_off = alloc_stack(tjit, nr_reg_args * sizeof(u64)); tjit->ip_off = alloc_stack(tjit, sizeof(u64)); @@ -2256,10 +2262,10 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, tjit->bpf_args_off = alloc_stack(tjit, nr_bpf_args * sizeof(u64)); tjit->retval_off = alloc_stack(tjit, sizeof(u64)); tjit->r7_r8_off = alloc_stack(tjit, 2 * sizeof(u64)); - tjit->r14_off = alloc_stack(tjit, sizeof(u64)); tjit->run_ctx_off = alloc_stack(tjit, sizeof(struct bpf_tramp_run_ctx)); tjit->tccnt_off = alloc_stack(tjit, sizeof(u64)); + tjit->r14_off = alloc_stack(tjit, sizeof(u64) * 2); /* * In accordance with the s390x ABI, the caller has allocated * STACK_FRAME_OVERHEAD bytes for us. 8 of them contain the caller's @@ -2268,8 +2274,13 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, tjit->stack_size -= STACK_FRAME_OVERHEAD - sizeof(u64); tjit->orig_stack_args_off = tjit->stack_size + STACK_FRAME_OVERHEAD; + /* lgr %r1,%r15 */ + EMIT4(0xb9040000, REG_1, REG_15); /* aghi %r15,-stack_size */ EMIT4_IMM(0xa70b0000, REG_15, -tjit->stack_size); + /* stg %r1,backchain_off(%r15) */ + EMIT6_DISP_LH(0xe3000000, 0x0024, REG_1, REG_0, REG_15, + tjit->backchain_off); /* mvc tccnt_off(4,%r15),stack_size+STK_OFF_TCCNT(%r15) */ _EMIT6(0xd203f000 | tjit->tccnt_off, 0xf000 | (tjit->stack_size + STK_OFF_TCCNT)); -- cgit