From nobody Thu Oct 9 14:39:51 2025 Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) (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 9340E2F0C40; Tue, 17 Jun 2025 22:51:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=216.40.44.10 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750200684; cv=none; b=Ro2iGnFhl/FKWSbDhtMb9U+ItZoCRRSd2Rn0ygR0tn3Mzi4MeKkPhCVQn0bFW2TsOSl+uOIz8F+8FOWO/TyxSDimgcSaHCGcX85gNycikQCYAaKPH7QXLmavh03LyPB94oHyZzv6fI2wzawHlgAAA53u+wQ698BeYUuh6tsaeBU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750200684; c=relaxed/simple; bh=ShUHp/wqwcY55c8QXwJf8hpQWS+ZW3po2DP2qOe02+A=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=V3zN/xDiNwzPdfM1aXlQSq0GZJN7tPWWGaxJ20OIsNWemJ/cOqx6YwirM7PR0TeJmZ4Z6am3Bb3KKt21IwNAl+Is9kKiha9mM4MWQVuKaiECCsF846tAn3B2KipWLo3lk5ezLK5DNNfZDNoHF/HdJCzru0OKhfUBvQnKCCqVa9Y= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org; spf=pass smtp.mailfrom=goodmis.org; arc=none smtp.client-ip=216.40.44.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=goodmis.org Received: from omf05.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id C6AD7161208; Tue, 17 Jun 2025 22:51:13 +0000 (UTC) Received: from [HIDDEN] (Authenticated sender: nevets@goodmis.org) by omf05.hostedemail.com (Postfix) with ESMTPA id B22A52000D; Tue, 17 Jun 2025 22:51:10 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.98.2) (envelope-from ) id 1uRf9B-00000002L3x-26IK; Tue, 17 Jun 2025 18:51:17 -0400 Message-ID: <20250617225117.349098754@goodmis.org> User-Agent: quilt/0.68 Date: Tue, 17 Jun 2025 18:50:11 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, bpf@vger.kernel.org, x86@kernel.org Cc: Masami Hiramatsu , Mathieu Desnoyers , Josh Poimboeuf , Peter Zijlstra , Ingo Molnar , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Andrii Nakryiko , Indu Bhagat , "Jose E. Marchesi" , Beau Belgrave , Jens Remus , Linus Torvalds , Andrew Morton Subject: [PATCH v6 02/12] unwind_user/sframe: Store sframe section data in per-mm maple tree References: <20250617225009.233007152@goodmis.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Rspamd-Queue-Id: B22A52000D X-Stat-Signature: ajzgg1xtm7q3jk6gayf448kbpdsyxm7f X-Rspamd-Server: rspamout06 X-Session-Marker: 6E657665747340676F6F646D69732E6F7267 X-Session-ID: U2FsdGVkX18ByZZco0tmx3xbfqiL1iYjHdAWST2LaG8= X-HE-Tag: 1750200670-644817 X-HE-Meta: U2FsdGVkX1+tfTKb/4tXNbkvF/yipibTe6D1HWtowO/5FCkAcu1jDfem9dZI+dF1xF31NGzWXtli3TqGpMzBN6TaSyq78CaZ/wJVuJF7nkK9qH/BXT1V7q/sxtZFcA3sEK++0fo4rta2755Uolv1BWNaDtYY5ipbYWUFtZ4WjT+twIoy60ZuPGbYNxkfc3sgMvD/Ui4XS5GBT+eDTMV6FA9W1JpVH6bpxoEqXko73j/AL5atz0WUgYvW34KtLHd49epvxpoVmR254sB+aGKrs/e3o/+kC1AbPK0F9Ky+WGvcEqaOWXQCtli3iEb5cx0G1+xMl4HRIxbUtYYnnaXnc5aTph9Jkl8ybC5x2Q0ggnxBUZfS/sUO+anRT6pAU1/6A7y69sgsF9cpRCf45fCvyI/uOwl9kdMYAwG8wpgFVLk= Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Josh Poimboeuf Associate an sframe section with its mm by adding it to a per-mm maple tree which is indexed by the corresponding text address range. A single sframe section can be associated with multiple text ranges. Signed-off-by: Josh Poimboeuf Signed-off-by: Steven Rostedt (Google) --- arch/x86/include/asm/mmu.h | 2 +- include/linux/mm_types.h | 3 +++ include/linux/sframe.h | 13 +++++++++ kernel/fork.c | 10 +++++++ kernel/unwind/sframe.c | 55 +++++++++++++++++++++++++++++++++++--- mm/init-mm.c | 2 ++ 6 files changed, 81 insertions(+), 4 deletions(-) diff --git a/arch/x86/include/asm/mmu.h b/arch/x86/include/asm/mmu.h index 0fe9c569d171..227a32899a59 100644 --- a/arch/x86/include/asm/mmu.h +++ b/arch/x86/include/asm/mmu.h @@ -87,7 +87,7 @@ typedef struct { .context =3D { \ .ctx_id =3D 1, \ .lock =3D __MUTEX_INITIALIZER(mm.context.lock), \ - } + }, =20 void leave_mm(void); #define leave_mm leave_mm diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h index d6b91e8a66d6..4296cabf4afa 100644 --- a/include/linux/mm_types.h +++ b/include/linux/mm_types.h @@ -1206,6 +1206,9 @@ struct mm_struct { #ifdef CONFIG_MM_ID mm_id_t mm_id; #endif /* CONFIG_MM_ID */ +#ifdef CONFIG_HAVE_UNWIND_USER_SFRAME + struct maple_tree sframe_mt; +#endif } __randomize_layout; =20 /* diff --git a/include/linux/sframe.h b/include/linux/sframe.h index 0584f661f698..73bf6f0b30c2 100644 --- a/include/linux/sframe.h +++ b/include/linux/sframe.h @@ -22,18 +22,31 @@ struct sframe_section { signed char fp_off; }; =20 +#define INIT_MM_SFRAME .sframe_mt =3D MTREE_INIT(sframe_mt, 0), +extern void sframe_free_mm(struct mm_struct *mm); + extern int sframe_add_section(unsigned long sframe_start, unsigned long sf= rame_end, unsigned long text_start, unsigned long text_end); extern int sframe_remove_section(unsigned long sframe_addr); =20 +static inline bool current_has_sframe(void) +{ + struct mm_struct *mm =3D current->mm; + + return mm && !mtree_empty(&mm->sframe_mt); +} + #else /* !CONFIG_HAVE_UNWIND_USER_SFRAME */ =20 +#define INIT_MM_SFRAME +static inline void sframe_free_mm(struct mm_struct *mm) {} static inline int sframe_add_section(unsigned long sframe_start, unsigned = long sframe_end, unsigned long text_start, unsigned long text_end) { return -ENOSYS; } static inline int sframe_remove_section(unsigned long sframe_addr) { retur= n -ENOSYS; } +static inline bool current_has_sframe(void) { return false; } =20 #endif /* CONFIG_HAVE_UNWIND_USER_SFRAME */ =20 diff --git a/kernel/fork.c b/kernel/fork.c index 3341d50c61f2..e56daf4e546f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -106,6 +106,7 @@ #include #include #include +#include =20 #include #include @@ -687,6 +688,7 @@ void __mmdrop(struct mm_struct *mm) mm_pasid_drop(mm); mm_destroy_cid(mm); percpu_counter_destroy_many(mm->rss_stat, NR_MM_COUNTERS); + sframe_free_mm(mm); =20 free_mm(mm); } @@ -1024,6 +1026,13 @@ static void mmap_init_lock(struct mm_struct *mm) #endif } =20 +static void mm_init_sframe(struct mm_struct *mm) +{ +#ifdef CONFIG_HAVE_UNWIND_USER_SFRAME + mt_init(&mm->sframe_mt); +#endif +} + static struct mm_struct *mm_init(struct mm_struct *mm, struct task_struct = *p, struct user_namespace *user_ns) { @@ -1053,6 +1062,7 @@ static struct mm_struct *mm_init(struct mm_struct *mm= , struct task_struct *p, mm->pmd_huge_pte =3D NULL; #endif mm_init_uprobes_state(mm); + mm_init_sframe(mm); hugetlb_count_init(mm); =20 if (current->mm) { diff --git a/kernel/unwind/sframe.c b/kernel/unwind/sframe.c index 20287f795b36..fa7d87ffd00a 100644 --- a/kernel/unwind/sframe.c +++ b/kernel/unwind/sframe.c @@ -122,15 +122,64 @@ int sframe_add_section(unsigned long sframe_start, un= signed long sframe_end, if (ret) goto err_free; =20 - /* TODO nowhere to store it yet - just free it and return an error */ - ret =3D -ENOSYS; + ret =3D mtree_insert_range(sframe_mt, sec->text_start, sec->text_end, sec= , GFP_KERNEL); + if (ret) { + dbg("mtree_insert_range failed: text=3D%lx-%lx\n", + sec->text_start, sec->text_end); + goto err_free; + } + + return 0; =20 err_free: free_section(sec); return ret; } =20 +static int __sframe_remove_section(struct mm_struct *mm, + struct sframe_section *sec) +{ + if (!mtree_erase(&mm->sframe_mt, sec->text_start)) { + dbg("mtree_erase failed: text=3D%lx\n", sec->text_start); + return -EINVAL; + } + + free_section(sec); + + return 0; +} + int sframe_remove_section(unsigned long sframe_start) { - return -ENOSYS; + struct mm_struct *mm =3D current->mm; + struct sframe_section *sec; + unsigned long index =3D 0; + bool found =3D false; + int ret =3D 0; + + mt_for_each(&mm->sframe_mt, sec, index, ULONG_MAX) { + if (sec->sframe_start =3D=3D sframe_start) { + found =3D true; + ret |=3D __sframe_remove_section(mm, sec); + } + } + + if (!found || ret) + return -EINVAL; + + return 0; +} + +void sframe_free_mm(struct mm_struct *mm) +{ + struct sframe_section *sec; + unsigned long index =3D 0; + + if (!mm) + return; + + mt_for_each(&mm->sframe_mt, sec, index, ULONG_MAX) + free_section(sec); + + mtree_destroy(&mm->sframe_mt); } diff --git a/mm/init-mm.c b/mm/init-mm.c index 4600e7605cab..b32fcf167cc2 100644 --- a/mm/init-mm.c +++ b/mm/init-mm.c @@ -11,6 +11,7 @@ #include #include #include +#include #include =20 #ifndef INIT_MM_CONTEXT @@ -46,6 +47,7 @@ struct mm_struct init_mm =3D { .user_ns =3D &init_user_ns, .cpu_bitmap =3D CPU_BITS_NONE, INIT_MM_CONTEXT(init_mm) + INIT_MM_SFRAME }; =20 void setup_initial_init_mm(void *start_code, void *end_code, --=20 2.47.2