From: Ankur Arora <ankur.a.arora@oracle.com> To: linux-kernel@vger.kernel.org, x86@kernel.org Cc: peterz@infradead.org, hpa@zytor.com, jpoimboe@redhat.com, namit@vmware.com, mhiramat@kernel.org, jgross@suse.com, bp@alien8.de, vkuznets@redhat.com, pbonzini@redhat.com, boris.ostrovsky@oracle.com, mihai.carabas@oracle.com, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, virtualization@lists.linux-foundation.org, Ankur Arora <ankur.a.arora@oracle.com> Subject: [RFC PATCH 10/26] x86/paravirt: Add primitives to stage pv-ops Date: Tue, 7 Apr 2020 22:03:07 -0700 [thread overview] Message-ID: <20200408050323.4237-11-ankur.a.arora@oracle.com> (raw) In-Reply-To: <20200408050323.4237-1-ankur.a.arora@oracle.com> Add paravirt_stage_alt() which conditionally selects between a paravirt or native pv-op and then stages it for later patching. Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> --- arch/x86/include/asm/paravirt_types.h | 6 +++ arch/x86/include/asm/text-patching.h | 3 ++ arch/x86/kernel/alternative.c | 58 +++++++++++++++++++++++++++ 3 files changed, 67 insertions(+) diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 3b9f6c105397..0c4ca7ad719c 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -350,6 +350,12 @@ extern struct paravirt_patch_template native_pv_ops; #define PARAVIRT_PATCH(x) \ (offsetof(struct paravirt_patch_template, x) / sizeof(void *)) +#define paravirt_stage_alt(do_stage, op, opfn) \ + (text_poke_pv_stage(PARAVIRT_PATCH(op), \ + (do_stage) ? (opfn) : (native_pv_ops.op))) + +#define paravirt_stage_zero() text_poke_pv_stage_zero() + /* * Neat trick to map patch type back to the call within the * corresponding structure. diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h index e2ef241c261e..706e61e6967d 100644 --- a/arch/x86/include/asm/text-patching.h +++ b/arch/x86/include/asm/text-patching.h @@ -55,6 +55,9 @@ extern void text_poke_bp(void *addr, const void *opcode, size_t len, const void extern void text_poke_queue(void *addr, const void *opcode, size_t len, const void *emulate); extern void text_poke_finish(void); +bool text_poke_pv_stage(u8 type, void *opfn); +void text_poke_pv_stage_zero(void); + #define INT3_INSN_SIZE 1 #define INT3_INSN_OPCODE 0xCC diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 8189ac21624c..0c335af9ee28 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -1307,3 +1307,61 @@ void __ref text_poke_bp(void *addr, const void *opcode, size_t len, const void * text_poke_loc_init(&tp, addr, opcode, len, emulate); text_poke_bp_batch(&tp, 1); } + +#ifdef CONFIG_PARAVIRT_RUNTIME +struct paravirt_stage_entry { + void *dest; /* pv_op destination */ + u8 type; /* pv_op type */ +}; + +/* + * We don't anticipate many pv-ops being written at runtime. + */ +#define PARAVIRT_STAGE_MAX 8 +struct paravirt_stage { + struct paravirt_stage_entry ops[PARAVIRT_STAGE_MAX]; + u32 count; +}; + +/* Protected by text_mutex */ +static struct paravirt_stage pv_stage; + +/** + * text_poke_pv_stage - Stage paravirt-op for poking. + * @addr: address in struct paravirt_patch_template + * @type: pv-op type + * @opfn: destination of the pv-op + * + * Return: staging status. + */ +bool text_poke_pv_stage(u8 type, void *opfn) +{ + if (system_state == SYSTEM_BOOTING) { /* Passthrough */ + PARAVIRT_PATCH_OP(pv_ops, type) = (long)opfn; + goto out; + } + + lockdep_assert_held(&text_mutex); + + if (PARAVIRT_PATCH_OP(pv_ops, type) == (long)opfn) + goto out; + + if (pv_stage.count >= PARAVIRT_STAGE_MAX) + goto out; + + pv_stage.ops[pv_stage.count].type = type; + pv_stage.ops[pv_stage.count].dest = opfn; + + pv_stage.count++; + + return true; +out: + return false; +} + +void text_poke_pv_stage_zero(void) +{ + lockdep_assert_held(&text_mutex); + pv_stage.count = 0; +} +#endif /* CONFIG_PARAVIRT_RUNTIME */ -- 2.20.1
WARNING: multiple messages have this Message-ID (diff)
From: Ankur Arora <ankur.a.arora@oracle.com> To: linux-kernel@vger.kernel.org, x86@kernel.org Cc: jgross@suse.com, xen-devel@lists.xenproject.org, kvm@vger.kernel.org, peterz@infradead.org, hpa@zytor.com, Ankur Arora <ankur.a.arora@oracle.com>, virtualization@lists.linux-foundation.org, pbonzini@redhat.com, namit@vmware.com, mhiramat@kernel.org, jpoimboe@redhat.com, mihai.carabas@oracle.com, bp@alien8.de, vkuznets@redhat.com, boris.ostrovsky@oracle.com Subject: [RFC PATCH 10/26] x86/paravirt: Add primitives to stage pv-ops Date: Tue, 7 Apr 2020 22:03:07 -0700 [thread overview] Message-ID: <20200408050323.4237-11-ankur.a.arora@oracle.com> (raw) In-Reply-To: <20200408050323.4237-1-ankur.a.arora@oracle.com> Add paravirt_stage_alt() which conditionally selects between a paravirt or native pv-op and then stages it for later patching. Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com> --- arch/x86/include/asm/paravirt_types.h | 6 +++ arch/x86/include/asm/text-patching.h | 3 ++ arch/x86/kernel/alternative.c | 58 +++++++++++++++++++++++++++ 3 files changed, 67 insertions(+) diff --git a/arch/x86/include/asm/paravirt_types.h b/arch/x86/include/asm/paravirt_types.h index 3b9f6c105397..0c4ca7ad719c 100644 --- a/arch/x86/include/asm/paravirt_types.h +++ b/arch/x86/include/asm/paravirt_types.h @@ -350,6 +350,12 @@ extern struct paravirt_patch_template native_pv_ops; #define PARAVIRT_PATCH(x) \ (offsetof(struct paravirt_patch_template, x) / sizeof(void *)) +#define paravirt_stage_alt(do_stage, op, opfn) \ + (text_poke_pv_stage(PARAVIRT_PATCH(op), \ + (do_stage) ? (opfn) : (native_pv_ops.op))) + +#define paravirt_stage_zero() text_poke_pv_stage_zero() + /* * Neat trick to map patch type back to the call within the * corresponding structure. diff --git a/arch/x86/include/asm/text-patching.h b/arch/x86/include/asm/text-patching.h index e2ef241c261e..706e61e6967d 100644 --- a/arch/x86/include/asm/text-patching.h +++ b/arch/x86/include/asm/text-patching.h @@ -55,6 +55,9 @@ extern void text_poke_bp(void *addr, const void *opcode, size_t len, const void extern void text_poke_queue(void *addr, const void *opcode, size_t len, const void *emulate); extern void text_poke_finish(void); +bool text_poke_pv_stage(u8 type, void *opfn); +void text_poke_pv_stage_zero(void); + #define INT3_INSN_SIZE 1 #define INT3_INSN_OPCODE 0xCC diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index 8189ac21624c..0c335af9ee28 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -1307,3 +1307,61 @@ void __ref text_poke_bp(void *addr, const void *opcode, size_t len, const void * text_poke_loc_init(&tp, addr, opcode, len, emulate); text_poke_bp_batch(&tp, 1); } + +#ifdef CONFIG_PARAVIRT_RUNTIME +struct paravirt_stage_entry { + void *dest; /* pv_op destination */ + u8 type; /* pv_op type */ +}; + +/* + * We don't anticipate many pv-ops being written at runtime. + */ +#define PARAVIRT_STAGE_MAX 8 +struct paravirt_stage { + struct paravirt_stage_entry ops[PARAVIRT_STAGE_MAX]; + u32 count; +}; + +/* Protected by text_mutex */ +static struct paravirt_stage pv_stage; + +/** + * text_poke_pv_stage - Stage paravirt-op for poking. + * @addr: address in struct paravirt_patch_template + * @type: pv-op type + * @opfn: destination of the pv-op + * + * Return: staging status. + */ +bool text_poke_pv_stage(u8 type, void *opfn) +{ + if (system_state == SYSTEM_BOOTING) { /* Passthrough */ + PARAVIRT_PATCH_OP(pv_ops, type) = (long)opfn; + goto out; + } + + lockdep_assert_held(&text_mutex); + + if (PARAVIRT_PATCH_OP(pv_ops, type) == (long)opfn) + goto out; + + if (pv_stage.count >= PARAVIRT_STAGE_MAX) + goto out; + + pv_stage.ops[pv_stage.count].type = type; + pv_stage.ops[pv_stage.count].dest = opfn; + + pv_stage.count++; + + return true; +out: + return false; +} + +void text_poke_pv_stage_zero(void) +{ + lockdep_assert_held(&text_mutex); + pv_stage.count = 0; +} +#endif /* CONFIG_PARAVIRT_RUNTIME */ -- 2.20.1
next prev parent reply other threads:[~2020-04-08 5:05 UTC|newest] Thread overview: 93+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-04-08 5:02 [RFC PATCH 00/26] Runtime paravirt patching Ankur Arora 2020-04-08 5:02 ` Ankur Arora 2020-04-08 5:02 ` [RFC PATCH 01/26] x86/paravirt: Specify subsection in PVOP macros Ankur Arora 2020-04-08 5:02 ` Ankur Arora 2020-04-08 5:02 ` [RFC PATCH 02/26] x86/paravirt: Allow paravirt patching post-init Ankur Arora 2020-04-08 5:02 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 03/26] x86/paravirt: PVRTOP macros for PARAVIRT_RUNTIME Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 04/26] x86/alternatives: Refactor alternatives_smp_module* Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 05/26] x86/alternatives: Rename alternatives_smp*, smp_alt_module Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 06/26] x86/alternatives: Remove stale symbols Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 07/26] x86/paravirt: Persist .parainstructions.runtime Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 08/26] x86/paravirt: Stash native pv-ops Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 09/26] x86/paravirt: Add runtime_patch() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 11:05 ` Peter Zijlstra 2020-04-08 11:05 ` Peter Zijlstra 2020-04-08 11:05 ` Peter Zijlstra 2020-04-08 5:03 ` Ankur Arora [this message] 2020-04-08 5:03 ` [RFC PATCH 10/26] x86/paravirt: Add primitives to stage pv-ops Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 11/26] x86/alternatives: Remove return value of text_poke*() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 12/26] x86/alternatives: Use __get_unlocked_pte() in text_poke() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 13/26] x86/alternatives: Split __text_poke() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 14/26] x86/alternatives: Handle native insns in text_poke_loc*() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 11:11 ` Peter Zijlstra 2020-04-08 11:11 ` Peter Zijlstra 2020-04-08 11:11 ` Peter Zijlstra 2020-04-08 11:17 ` Peter Zijlstra 2020-04-08 11:17 ` Peter Zijlstra 2020-04-08 11:17 ` Peter Zijlstra 2020-04-08 5:03 ` [RFC PATCH 15/26] x86/alternatives: Non-emulated text poking Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 11:13 ` Peter Zijlstra 2020-04-08 11:13 ` Peter Zijlstra 2020-04-08 11:13 ` Peter Zijlstra 2020-04-08 11:23 ` Peter Zijlstra 2020-04-08 11:23 ` Peter Zijlstra 2020-04-08 11:23 ` Peter Zijlstra 2020-04-08 5:03 ` [RFC PATCH 16/26] x86/alternatives: Add paravirt patching at runtime Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 17/26] x86/alternatives: Add patching logic in text_poke_site() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 18/26] x86/alternatives: Handle BP in non-emulated text poking Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 19/26] x86/alternatives: NMI safe runtime patching Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 11:36 ` Peter Zijlstra 2020-04-08 11:36 ` Peter Zijlstra 2020-04-08 11:36 ` Peter Zijlstra 2020-04-08 5:03 ` [RFC PATCH 20/26] x86/paravirt: Enable pv-spinlocks in runtime_patch() Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 21/26] x86/alternatives: Paravirt runtime selftest Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 22/26] kvm/paravirt: Encapsulate KVM pv switching logic Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 23/26] x86/kvm: Add worker to trigger runtime patching Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 24/26] x86/kvm: Support dynamic CPUID hints Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 25/26] x86/kvm: Guest support for dynamic hints Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 5:03 ` [RFC PATCH 26/26] x86/kvm: Add hint change notifier for KVM_HINT_REALTIME Ankur Arora 2020-04-08 5:03 ` Ankur Arora 2020-04-08 12:08 ` [RFC PATCH 00/26] Runtime paravirt patching Peter Zijlstra 2020-04-08 12:08 ` Peter Zijlstra 2020-04-08 12:08 ` Peter Zijlstra 2020-04-08 13:33 ` Jürgen Groß 2020-04-08 13:33 ` Jürgen Groß 2020-04-08 14:49 ` Peter Zijlstra 2020-04-08 14:49 ` Peter Zijlstra 2020-04-08 14:49 ` Peter Zijlstra 2020-04-10 9:18 ` Ankur Arora 2020-04-10 9:18 ` Ankur Arora 2020-04-08 12:28 ` Jürgen Groß 2020-04-08 12:28 ` Jürgen Groß 2020-04-10 7:56 ` Ankur Arora 2020-04-10 7:56 ` Ankur Arora 2020-04-10 9:32 ` Ankur Arora 2020-04-10 9:32 ` Ankur Arora 2020-04-08 14:12 ` Thomas Gleixner 2020-04-08 14:12 ` Thomas Gleixner 2020-04-08 14:12 ` Thomas Gleixner 2020-04-10 9:55 ` Ankur Arora 2020-04-10 9:55 ` Ankur Arora
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