From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 95427849C; Sun, 30 Nov 2025 18:54:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764528855; cv=none; b=hO/mG5qG2+u3L/PmQ8mZ0umL7/A0GFimQc7PxhIBSxq2U9hXCI8NPn2X+LFWcFRXtI9KlKFg7KIl78/eP5KfXoHQNQ4NDvhtsq4N1By7/BmUcz93EKCQp+IMfkVvF3gRMGoj63NIehpKEnrSXEmvt3hdIM+l5RDc1sUnSdNxb5I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764528855; c=relaxed/simple; bh=AaNISiBhTaDztZj+M+SdnDxDNolwUilSkjzHeNb5Qx4=; h=Date:Message-ID:From:To:Cc:Subject:In-Reply-To:References: MIME-Version:Content-Type; b=hK6caAm8Vxk5zN//Pejv8tgVpJ+CMbkAjf4woMCtfOVBOpEeOUq60zjEl0L2qWRbDYIfeQlu7yciUzz+ueljgfjb4Q9Uneh8t8HCWS3qfqO+hfbR76WzMjOQU6Yq8wd93SgviQGMsKITeNhCyLzFiF5tBSe175su4pcn32U5Xe0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BxdMgT4H; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BxdMgT4H" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1755AC4CEF8; Sun, 30 Nov 2025 18:54:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764528855; bh=AaNISiBhTaDztZj+M+SdnDxDNolwUilSkjzHeNb5Qx4=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=BxdMgT4HVPGwZb1lUH73DNO50L9pICnJ1fDAr0EjCbMlwvXb0t9ESuAYt/jiQNF2D K3/2iCI8mpAOYaJ3G7Uc0zvmgZeH1HcMygI2nZHVYlNOc0zz8OD5tGT9q8UbiR0RII 8Z2Biio1DtlSPUyf5BBcULMpB5h+T4z/mXgykeg6AnzJF1mviyZ0TvhKeNptpRftlK g9OdcdeVaASo3tjJi5FMJ06QduWedEnhhN3iG2xhac/LimQfyiOlKUq3PldZs+J6J1 mXY8XPTSv8Lif/SMhryNHML3M/DMQBUEKRtuzmYbAB89O2X+QACllQnLK3z/RTMjO1 nqUGGptd81crg== Received: from sofa.misterjones.org ([185.219.108.64] helo=lobster-girl.misterjones.org) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1vPmYm-00000009RYR-3DxY; Sun, 30 Nov 2025 18:54:12 +0000 Date: Sun, 30 Nov 2025 18:54:12 +0000 Message-ID: <874iqbfj1n.wl-maz@kernel.org> From: Marc Zyngier To: Vincent Donnefort Cc: rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, jstultz@google.com, qperret@google.com, will@kernel.org, aneesh.kumar@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v8 25/28] KVM: arm64: Add event support to the pKVM hyp and trace remote In-Reply-To: <20251107093840.3779150-26-vdonnefort@google.com> References: <20251107093840.3779150-1-vdonnefort@google.com> <20251107093840.3779150-26-vdonnefort@google.com> User-Agent: Wanderlust/2.15.9 (Almost Unreal) SEMI-EPG/1.14.7 (Harue) FLIM-LB/1.14.9 (=?UTF-8?B?R29qxY0=?=) APEL-LB/10.8 EasyPG/1.0.0 Emacs/30.1 (aarch64-unknown-linux-gnu) MULE/6.0 (HANACHIRUSATO) Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset=US-ASCII X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: vdonnefort@google.com, rostedt@goodmis.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-trace-kernel@vger.kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, jstultz@google.com, qperret@google.com, will@kernel.org, aneesh.kumar@kernel.org, kernel-team@android.com, linux-kernel@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false On Fri, 07 Nov 2025 09:38:37 +0000, Vincent Donnefort wrote: > > Allow the creation of hypervisor and trace remote events with a single > macro HYP_EVENT(). That macro expands in the kernel side to add all > the required declarations (based on REMOTE_EVENT()) as well as in the > hypervisor side to create the trace_() function. > > Signed-off-by: Vincent Donnefort > > diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h > index 4faabf398881..f7b29eae7010 100644 > --- a/arch/arm64/include/asm/kvm_asm.h > +++ b/arch/arm64/include/asm/kvm_asm.h > @@ -95,6 +95,7 @@ enum __kvm_host_smccc_func { > __KVM_HOST_SMCCC_FUNC___pkvm_enable_tracing, > __KVM_HOST_SMCCC_FUNC___pkvm_reset_tracing, > __KVM_HOST_SMCCC_FUNC___pkvm_swap_reader_tracing, > + __KVM_HOST_SMCCC_FUNC___pkvm_enable_event, nit: add 'tracing' to the name of the function, like its little friends. Saves us from wondering whether this is about PMU events or not... > }; > > #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] > diff --git a/arch/arm64/include/asm/kvm_define_hypevents.h b/arch/arm64/include/asm/kvm_define_hypevents.h > new file mode 100644 > index 000000000000..0ef5a9eefcbe > --- /dev/null > +++ b/arch/arm64/include/asm/kvm_define_hypevents.h > @@ -0,0 +1,21 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#ifndef HYP_EVENT_FILE > +# undef __ARM64_KVM_HYPEVENTS_H_ > +# define REMOTE_EVENT_INCLUDE_FILE arch/arm64/include/asm/kvm_hypevents.h > +#else > +# define REMOTE_EVENT_INCLUDE_FILE HYP_EVENT_FILE > +#endif I'm feeling a bit sick here. Can you please document here how the whole repainting trickery works, how the event equivalence works, and what the whole thing depends on? I *really* don't want to have to reverse engineer this stuff when it will break. > + > +#define REMOTE_EVENT_SECTION "_hyp_events" > + > +#define HE_STRUCT(__args) __args > +#define HE_PRINTK(__args...) __args > +#define he_field re_field > + > +#define HYP_EVENT(__name, __proto, __struct, __assign, __printk) \ > + REMOTE_EVENT(__name, 0, RE_STRUCT(__struct), RE_PRINTK(__printk)) > + > +#define HYP_EVENT_MULTI_READ > + > +#include > diff --git a/arch/arm64/include/asm/kvm_hypevents.h b/arch/arm64/include/asm/kvm_hypevents.h > new file mode 100644 > index 000000000000..d6e033c96c52 > --- /dev/null > +++ b/arch/arm64/include/asm/kvm_hypevents.h > @@ -0,0 +1,10 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#if !defined(__ARM64_KVM_HYPEVENTS_H_) || defined(HYP_EVENT_MULTI_READ) > +#define __ARM64_KVM_HYPEVENTS_H_ > + > +#ifdef __KVM_NVHE_HYPERVISOR__ > +#include > +#endif > + > +#endif > diff --git a/arch/arm64/include/asm/kvm_hyptrace.h b/arch/arm64/include/asm/kvm_hyptrace.h > index 9c30a479bc36..d6e0953a07d6 100644 > --- a/arch/arm64/include/asm/kvm_hyptrace.h > +++ b/arch/arm64/include/asm/kvm_hyptrace.h > @@ -10,4 +10,17 @@ struct hyp_trace_desc { > struct trace_buffer_desc trace_buffer_desc; > > }; > + > +struct hyp_event_id { > + unsigned short id; > + void *data; > +}; > + > +extern struct remote_event __hyp_events_start[]; > +extern struct remote_event __hyp_events_end[]; > + > +/* hyp_event section used by the hypervisor */ > +extern struct hyp_event_id __hyp_event_ids_start[]; > +extern struct hyp_event_id __hyp_event_ids_end[]; > + > #endif > diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h > index 5369763606e7..c0efa9aa541b 100644 > --- a/arch/arm64/kernel/image-vars.h > +++ b/arch/arm64/kernel/image-vars.h > @@ -137,6 +137,10 @@ KVM_NVHE_ALIAS(__hyp_data_start); > KVM_NVHE_ALIAS(__hyp_data_end); > KVM_NVHE_ALIAS(__hyp_rodata_start); > KVM_NVHE_ALIAS(__hyp_rodata_end); > +#ifdef CONFIG_PKVM_TRACING > +KVM_NVHE_ALIAS(__hyp_event_ids_start); > +KVM_NVHE_ALIAS(__hyp_event_ids_end); > +#endif > > /* pKVM static key */ > KVM_NVHE_ALIAS(kvm_protected_mode_initialized); > diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S > index ad6133b89e7a..0e201a3c8de5 100644 > --- a/arch/arm64/kernel/vmlinux.lds.S > +++ b/arch/arm64/kernel/vmlinux.lds.S > @@ -13,12 +13,23 @@ > *(__kvm_ex_table) \ > __stop___kvm_ex_table = .; > > +#ifdef CONFIG_PKVM_TRACING > +#define HYPERVISOR_EVENT_IDS \ > + . = ALIGN(PAGE_SIZE); \ > + __hyp_event_ids_start = .; \ > + *(HYP_SECTION_NAME(.event_ids)) \ > + __hyp_event_ids_end = .; > +#else > +#define HYPERVISOR_EVENT_IDS > +#endif > + > #define HYPERVISOR_RODATA_SECTIONS \ > HYP_SECTION_NAME(.rodata) : { \ > . = ALIGN(PAGE_SIZE); \ > __hyp_rodata_start = .; \ > *(HYP_SECTION_NAME(.data..ro_after_init)) \ > *(HYP_SECTION_NAME(.rodata)) \ > + HYPERVISOR_EVENT_IDS \ > . = ALIGN(PAGE_SIZE); \ > __hyp_rodata_end = .; \ > } > @@ -307,6 +318,13 @@ SECTIONS > > HYPERVISOR_DATA_SECTION > > +#ifdef CONFIG_PKVM_TRACING > + .data.hyp_events : { > + __hyp_events_start = .; > + *(SORT(_hyp_events.*)) > + __hyp_events_end = .; > + } > +#endif > /* > * Data written with the MMU off but read with the MMU on requires > * cache lines to be invalidated, discarding up to a Cache Writeback > diff --git a/arch/arm64/kvm/hyp/include/nvhe/define_events.h b/arch/arm64/kvm/hyp/include/nvhe/define_events.h > new file mode 100644 > index 000000000000..2298b49cb355 > --- /dev/null > +++ b/arch/arm64/kvm/hyp/include/nvhe/define_events.h > @@ -0,0 +1,21 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > + > +#ifndef HYP_EVENT_FILE > +# define __HYP_EVENT_FILE > +#else > +# define __HYP_EVENT_FILE __stringify(HYP_EVENT_FILE) > +#endif > + > +#undef HYP_EVENT > +#define HYP_EVENT(__name, __proto, __struct, __assign, __printk) \ > + atomic_t __ro_after_init __name##_enabled = ATOMIC_INIT(0); \ > + struct hyp_event_id hyp_event_id_##__name \ > + __section(".hyp.event_ids."#__name) = { \ > + .data = (void *)&__name##_enabled, \ > + } > + > +#define HYP_EVENT_MULTI_READ > +#include __HYP_EVENT_FILE > +#undef HYP_EVENT_MULTI_READ > + > +#undef HYP_EVENT > diff --git a/arch/arm64/kvm/hyp/include/nvhe/trace.h b/arch/arm64/kvm/hyp/include/nvhe/trace.h > index 0d2732f0d406..f7b286e92853 100644 > --- a/arch/arm64/kvm/hyp/include/nvhe/trace.h > +++ b/arch/arm64/kvm/hyp/include/nvhe/trace.h > @@ -1,21 +1,52 @@ > /* SPDX-License-Identifier: GPL-2.0-only */ > #ifndef __ARM64_KVM_HYP_NVHE_TRACE_H > #define __ARM64_KVM_HYP_NVHE_TRACE_H > + > +#include > + > #include > > +#define HE_PROTO(__args...) __args > + > #ifdef CONFIG_PKVM_TRACING > void *tracing_reserve_entry(unsigned long length); > void tracing_commit_entry(void); > > +#define HE_ASSIGN(__args...) __args > +#define HE_STRUCT RE_STRUCT > +#define he_field re_field > + > +#define HYP_EVENT(__name, __proto, __struct, __assign, __printk) \ > + REMOTE_EVENT_FORMAT(__name, __struct); \ > + extern atomic_t __name##_enabled; \ > + extern struct hyp_event_id hyp_event_id_##__name; \ > + static __always_inline void trace_##__name(__proto) \ > + { \ > + struct remote_event_format_##__name *__entry; \ > + size_t length = sizeof(*__entry); \ > + \ > + if (!atomic_read(&__name##_enabled)) \ > + return; \ > + __entry = tracing_reserve_entry(length); \ > + if (!__entry) \ > + return; \ > + __entry->hdr.id = hyp_event_id_##__name.id; \ > + __assign \ > + tracing_commit_entry(); \ > + } > + > void __pkvm_update_clock_tracing(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc); > int __pkvm_load_tracing(unsigned long desc_va, size_t desc_size); > void __pkvm_unload_tracing(void); > int __pkvm_enable_tracing(bool enable); > int __pkvm_reset_tracing(unsigned int cpu); > int __pkvm_swap_reader_tracing(unsigned int cpu); > +int __pkvm_enable_event(unsigned short id, bool enable); > #else > static inline void *tracing_reserve_entry(unsigned long length) { return NULL; } > static inline void tracing_commit_entry(void) { } > +#define HYP_EVENT(__name, __proto, __struct, __assign, __printk) \ > + static inline void trace_##__name(__proto) {} > > static inline > void __pkvm_update_clock_tracing(u32 mult, u32 shift, u64 epoch_ns, u64 epoch_cyc) { } > @@ -24,5 +55,6 @@ static inline void __pkvm_unload_tracing(void) { } > static inline int __pkvm_enable_tracing(bool enable) { return -ENODEV; } > static inline int __pkvm_reset_tracing(unsigned int cpu) { return -ENODEV; } > static inline int __pkvm_swap_reader_tracing(unsigned int cpu) { return -ENODEV; } > +static inline int __pkvm_enable_event(unsigned short id, bool enable) { return -ENODEV; } > #endif > #endif > diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile > index 504c3b9caef8..b77959e963f3 100644 > --- a/arch/arm64/kvm/hyp/nvhe/Makefile > +++ b/arch/arm64/kvm/hyp/nvhe/Makefile > @@ -29,7 +29,7 @@ hyp-obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ > ../fpsimd.o ../hyp-entry.o ../exception.o ../pgtable.o > hyp-obj-y += ../../../kernel/smccc-call.o > hyp-obj-$(CONFIG_LIST_HARDENED) += list_debug.o > -hyp-obj-$(CONFIG_PKVM_TRACING) += clock.o trace.o ../../../../../kernel/trace/simple_ring_buffer.o > +hyp-obj-$(CONFIG_PKVM_TRACING) += clock.o trace.o ../../../../../kernel/trace/simple_ring_buffer.o events.o > hyp-obj-y += $(lib-objs) > > ## > diff --git a/arch/arm64/kvm/hyp/nvhe/events.c b/arch/arm64/kvm/hyp/nvhe/events.c > new file mode 100644 > index 000000000000..5905b42cb0d0 > --- /dev/null > +++ b/arch/arm64/kvm/hyp/nvhe/events.c > @@ -0,0 +1,36 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2025 Google LLC > + * Author: Vincent Donnefort > + */ > + > +#include > +#include > + > +#include > + > +extern struct hyp_event_id __hyp_event_ids_start[]; > +extern struct hyp_event_id __hyp_event_ids_end[]; Isn't that already declared in an include file? > + > +int __pkvm_enable_event(unsigned short id, bool enable) > +{ > + struct hyp_event_id *event_id = __hyp_event_ids_start; > + atomic_t *enable_key; > + > + for (; (unsigned long)event_id < (unsigned long)__hyp_event_ids_end; > + event_id++) { > + if (event_id->id != id) > + continue; > + > + enable_key = (atomic_t *)event_id->data; > + enable_key = hyp_fixmap_map(__hyp_pa(enable_key)); > + > + atomic_set(enable_key, enable); > + > + hyp_fixmap_unmap(); > + > + return 0; > + } > + > + return -EINVAL; > +} > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c > index 8adad701fc76..5e4b519e5204 100644 > --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c > +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c > @@ -634,6 +634,14 @@ static void handle___pkvm_swap_reader_tracing(struct kvm_cpu_context *host_ctxt) > cpu_reg(host_ctxt, 1) = __pkvm_swap_reader_tracing(cpu); > } > > +static void handle___pkvm_enable_event(struct kvm_cpu_context *host_ctxt) > +{ > + DECLARE_REG(unsigned short, id, host_ctxt, 1); > + DECLARE_REG(bool, enable, host_ctxt, 2); > + > + cpu_reg(host_ctxt, 1) = __pkvm_enable_event(id, enable); > +} > + > typedef void (*hcall_t)(struct kvm_cpu_context *); > > #define HANDLE_FUNC(x) [__KVM_HOST_SMCCC_FUNC_##x] = (hcall_t)handle_##x > @@ -681,6 +689,7 @@ static const hcall_t host_hcall[] = { > HANDLE_FUNC(__pkvm_enable_tracing), > HANDLE_FUNC(__pkvm_reset_tracing), > HANDLE_FUNC(__pkvm_swap_reader_tracing), > + HANDLE_FUNC(__pkvm_enable_event), > }; > > static void handle_host_hcall(struct kvm_cpu_context *host_ctxt) > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S > index d724f6d69302..a68411bf4bef 100644 > --- a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S > +++ b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S > @@ -16,6 +16,12 @@ SECTIONS { > HYP_SECTION(.text) > HYP_SECTION(.data..ro_after_init) > HYP_SECTION(.rodata) > +#ifdef CONFIG_PKVM_TRACING > + . = ALIGN(PAGE_SIZE); > + BEGIN_HYP_SECTION(.event_ids) > + *(SORT(.hyp.event_ids.*)) > + END_HYP_SECTION > +#endif > > /* > * .hyp..data..percpu needs to be page aligned to maintain the same > diff --git a/arch/arm64/kvm/hyp_trace.c b/arch/arm64/kvm/hyp_trace.c > index 1062b4310f8c..73539f5b5e42 100644 > --- a/arch/arm64/kvm/hyp_trace.c > +++ b/arch/arm64/kvm/hyp_trace.c > @@ -307,7 +307,7 @@ static int hyp_trace_reset(unsigned int cpu, void *priv) > > static int hyp_trace_enable_event(unsigned short id, bool enable, void *priv) > { > - return 0; > + return kvm_call_hyp_nvhe(__pkvm_enable_event, id, enable); > } > > static int hyp_trace_clock_show(struct seq_file *m, void *v) > @@ -334,10 +334,27 @@ static struct trace_remote_callbacks trace_remote_callbacks = { > .enable_event = hyp_trace_enable_event, > }; > > +#include > + > +static void hyp_trace_init_events(void) > +{ > + struct hyp_event_id *hyp_event_id = __hyp_event_ids_start; > + struct remote_event *event = __hyp_events_start; > + int id = 0; > + > + /* Events on both sides hypervisor are sorted */ > + for (; (unsigned long)event < (unsigned long)__hyp_events_end; It feels very bizarre that you have to cast anything here. Aren't the two variables of the same type, part of the same array, and shouldn't pointer arithmetic apply? > + event++, hyp_event_id++, id++) > + event->id = hyp_event_id->id = id; > +} > + > int hyp_trace_init(void) > { > if (!is_protected_kvm_enabled()) > return 0; > > - return trace_remote_register("hypervisor", &trace_remote_callbacks, &trace_buffer, NULL, 0); > + hyp_trace_init_events(); > + > + return trace_remote_register("hypervisor", &trace_remote_callbacks, &trace_buffer, > + __hyp_events_start, __hyp_events_end - __hyp_events_start); > } > diff --git a/kernel/trace/trace_remote.c b/kernel/trace/trace_remote.c > index 4f2b67d1bfec..e54cc3e75dc5 100644 > --- a/kernel/trace/trace_remote.c > +++ b/kernel/trace/trace_remote.c > @@ -1040,7 +1040,7 @@ static int remote_event_format_show(struct seq_file *s, void *unused) > while (field->name) { > seq_printf(s, "\tfield:%s %s;\toffset:%zu;\tsize:%u;\tsigned:%d;\n", > field->type, field->name, offset, field->size, > - !field->is_signed); > + field->is_signed); > offset += field->size; > field++; > } > @@ -1071,7 +1071,7 @@ static int remote_event_callback(const char *name, umode_t *mode, void **data, > > if (!strcmp(name, "format")) { > *mode = TRACEFS_MODE_READ; > - *fops = &remote_event_id_fops; > + *fops = &remote_event_format_fops; > return 1; > } > Thanks, M. -- Jazz isn't dead. It just smells funny.