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From: youling 257 <youling257@gmail.com>
To: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Alexei Starovoitov <ast@kernel.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	Andrey Konovalov <andreyknvl@google.com>,
	Andy Lutomirski <luto@kernel.org>, Arnd Bergmann <arnd@arndb.de>,
	Borislav Petkov <bp@alien8.de>, Christoph Hellwig <hch@lst.de>,
	Christoph Lameter <cl@linux.com>,
	David Rientjes <rientjes@google.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Eric Biggers <ebiggers@kernel.org>,
	Eric Dumazet <edumazet@google.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Herbert Xu <herbert@gondor.apana.org.au>,
	Ilya Leoshkevich <iii@linux.ibm.com>,
	Ingo Molnar <mingo@redhat.com>, Jens Axboe <axboe@kernel.dk>,
	Joonsoo Kim <iamjoonsoo.kim@lge.com>,
	Kees Cook <keescook@chromium.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Matthew Wilcox <willy@infradead.org>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Pekka Enberg <penberg@kernel.org>,
	Peter Zijlstra <peterz@infradead.org>,
	Petr Mladek <pmladek@suse.com>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Steven Rostedt <rostedt@goodmis.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Vegard Nossum <vegard.nossum@oracle.com>,
	Vlastimil Babka <vbabka@suse.cz>,
	kasan-dev@googlegroups.com, linux-mm@kvack.org,
	linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v7 18/43] instrumented.h: add KMSAN support
Date: Fri, 21 Oct 2022 13:55:06 +0800	[thread overview]
Message-ID: <CAOzgRdb+W3_FuOB+P_HkeinDiJdgpQSsXMC4GArOSixL9K5avg@mail.gmail.com> (raw)
In-Reply-To: <CAG_fn=WLRN=C1rKrpq4=d=AO9dBaGxoa6YsG7+KrqAck5Bty0Q@mail.gmail.com>

How to use perf tool?
I use diff compare "nm -S vmlinux".
android_x86:/ $ su
android_x86:/ # diff /sdcard/with_vmlinux /sdcard/without_vmlinux
--- /sdcard/with_vmlinux
+++ /sdcard/without_vmlinux
@@ -12951,7 +12951,7 @@
 ffffffff81338400 00000000000000dc T compat_only_sysfs_link_entry_to_kobj
 ffffffff810884d0 00000000000002b7 T compat_ptrace_request
 ffffffff812b4e80 0000000000000025 T compat_ptr_ioctl
-ffffffff811380d0 000000000000008d T compat_put_bitmap
+ffffffff811380d0 000000000000008a T compat_put_bitmap
 ffffffff81a62180 000000000000000f t compat_raw_ioctl
 ffffffff81afa060 000000000000000f t compat_rawv6_ioctl
 ffffffff81090790 0000000000000018 T compat_restore_altstack
@@ -14260,7 +14260,7 @@
 ffffffff8167d380 00000000000000dd T cppc_set_enable
 ffffffff8167d460 0000000000000221 T cppc_set_perf
 ffffffff818cdbe0 000000000000004f t cppc_update_perf
-ffffffff8102bba0 000000000000012b t cp_stat64
+ffffffff8102bba0 000000000000012a t cp_stat64
 ffffffff81494810 0000000000000028 t cp_status_show
 ffffffff812a33e0 00000000000001b2 t cp_statx
 ffffffff82e1c934 0000000000000004 b cpu0_hotpluggable
@@ -26993,7 +26993,6 @@
 ffffffff821b8000 0000000000000038 d CSWTCH.102
 ffffffff821cd6c0 0000000000000048 d CSWTCH.107
 ffffffff821d4b80 0000000000000018 d CSWTCH.11
-ffffffff8203dd88 000000000000000c d CSWTCH.111
 ffffffff82152de0 00000000000000a0 d CSWTCH.111
 ffffffff82105ea0 0000000000000020 d CSWTCH.1116
 ffffffff82105e80 0000000000000020 d CSWTCH.1121
@@ -27002,6 +27001,7 @@
 ffffffff821d4b60 0000000000000018 d CSWTCH.12
 ffffffff821b2c60 0000000000000024 d CSWTCH.120
 ffffffff82033fc0 0000000000000068 d CSWTCH.123
+ffffffff8203dd88 000000000000000c d CSWTCH.123
 ffffffff82014b80 00000000000000a0 d CSWTCH.125
 ffffffff82014b40 0000000000000028 d CSWTCH.128
 ffffffff82033f40 0000000000000064 d CSWTCH.128
@@ -27026,7 +27026,6 @@
 ffffffff821c9b80 0000000000000018 d CSWTCH.189
 ffffffff821b39a0 0000000000000028 d CSWTCH.19
 ffffffff820055c0 0000000000000024 d CSWTCH.195
-ffffffff82208de0 0000000000000004 d CSWTCH.199
 ffffffff82146127 0000000000000006 d CSWTCH.2
 ffffffff82146380 0000000000000014 d CSWTCH.2
 ffffffff8219f770 0000000000000018 d CSWTCH.20
@@ -27033,5 +27032,6 @@
 ffffffff821d9c90 0000000000000018 d CSWTCH.20
 ffffffff821b7e60 0000000000000128 d CSWTCH.202
+ffffffff82208de0 0000000000000004 d CSWTCH.202
 ffffffff821b7cc0 0000000000000188 d CSWTCH.204
 ffffffff821b7c80 0000000000000038 d CSWTCH.206
 ffffffff821a4ac0 0000000000000006 d CSWTCH.207
@@ -27043,8 +27043,8 @@
 ffffffff821b7be0 0000000000000038 d CSWTCH.214
 ffffffff821c9940 0000000000000030 d CSWTCH.217
 ffffffff8219f750 0000000000000018 d CSWTCH.22
-ffffffff82033580 0000000000000023 d CSWTCH.221
 ffffffff8213de80 0000000000000028 d CSWTCH.222
+ffffffff82033580 0000000000000023 d CSWTCH.223
 ffffffff82216c10 0000000000000014 d CSWTCH.225
 ffffffff82216bf0 0000000000000014 d CSWTCH.232
 ffffffff82216be0 0000000000000010 d CSWTCH.234
@@ -27052,7 +27052,7 @@
 ffffffff821b3800 0000000000000188 d CSWTCH.24
 ffffffff821f3340 0000000000000058 d CSWTCH.242
 ffffffff82158c60 0000000000000030 d CSWTCH.244
-ffffffff821a9868 000000000000000a d CSWTCH.255
+ffffffff821a9868 000000000000000a d CSWTCH.258
 ffffffff82106a20 0000000000000010 d CSWTCH.261
 ffffffff821a42a0 0000000000000004 d CSWTCH.261
 ffffffff8203d9e0 0000000000000030 d CSWTCH.265
@@ -27059,12 +27059,12 @@
 ffffffff82126780 0000000000000028 d CSWTCH.27
 ffffffff8214d360 0000000000000040 d CSWTCH.278
 ffffffff82136f80 0000000000000024 d CSWTCH.28
-ffffffff821b3000 0000000000000024 d CSWTCH.281
-ffffffff821b2fc0 0000000000000024 d CSWTCH.282
-ffffffff8210ed40 000000000000002c d CSWTCH.289
-ffffffff8210ed00 000000000000002b d CSWTCH.290
-ffffffff8210ecc0 000000000000002c d CSWTCH.292
+ffffffff821b3000 0000000000000024 d CSWTCH.285
+ffffffff821b2fc0 0000000000000024 d CSWTCH.286
+ffffffff8210ed40 000000000000002c d CSWTCH.292
 ffffffff821b3ae0 0000000000000020 d CSWTCH.292
+ffffffff8210ed00 000000000000002b d CSWTCH.293
+ffffffff8210ecc0 000000000000002c d CSWTCH.295
 ffffffff8214d340 0000000000000020 d CSWTCH.296
 ffffffff82146121 0000000000000006 d CSWTCH.3
 ffffffff821b7ba0 0000000000000020 d CSWTCH.3
@@ -27075,17 +27075,17 @@
 ffffffff821d3c40 0000000000000020 d CSWTCH.31
 ffffffff820ff780 0000000000000004 d CSWTCH.318
 ffffffff821b5cc0 0000000000000038 d CSWTCH.33
-ffffffff8214efa0 0000000000000010 d CSWTCH.334
+ffffffff8214efa0 0000000000000010 d CSWTCH.346
 ffffffff8214a8c0 0000000000000018 d CSWTCH.35
-ffffffff8210ecb0 000000000000000c d CSWTCH.359
-ffffffff8202cae0 000000000000002c d CSWTCH.360
+ffffffff8210ecb0 000000000000000c d CSWTCH.362
 ffffffff82016300 0000000000000020 d CSWTCH.363
 ffffffff821fce00 0000000000000040 d CSWTCH.38
-ffffffff82032780 0000000000000074 d CSWTCH.387
+ffffffff8202cae0 000000000000002c d CSWTCH.381
+ffffffff82032780 0000000000000074 d CSWTCH.390
 ffffffff82118100 0000000000000018 d CSWTCH.40
 ffffffff821598a0 0000000000000020 d CSWTCH.41
-ffffffff82032760 0000000000000020 d CSWTCH.428
 ffffffff82139a20 0000000000000038 d CSWTCH.43
+ffffffff82032760 0000000000000020 d CSWTCH.431
 ffffffff82015d40 0000000000000040 d CSWTCH.45
 ffffffff821399e0 0000000000000040 d CSWTCH.45
 ffffffff822194e0 000000000000000c d CSWTCH.450
@@ -27092,5 +27092,5 @@
 ffffffff8214d2e0 0000000000000048 d CSWTCH.459
-ffffffff8210eca0 000000000000000c d CSWTCH.464
+ffffffff8210eca0 000000000000000c d CSWTCH.467
 ffffffff821399c0 0000000000000020 d CSWTCH.47
 ffffffff8214a8e0 00000000000000c8 d CSWTCH.48
 ffffffff82028ac0 0000000000000018 d CSWTCH.49
@@ -27097,8 +27097,8 @@
 ffffffff821399a0 0000000000000020 d CSWTCH.49
-ffffffff82032740 0000000000000018 d CSWTCH.507
-ffffffff82032730 000000000000000c d CSWTCH.508
-ffffffff82032720 000000000000000c d CSWTCH.509
 ffffffff82139960 0000000000000030 d CSWTCH.51
+ffffffff82032740 0000000000000018 d CSWTCH.510
+ffffffff82032730 000000000000000c d CSWTCH.511
+ffffffff82032720 000000000000000c d CSWTCH.512
 ffffffff821595c0 0000000000000100 d CSWTCH.52
 ffffffff821b6240 0000000000000018 d CSWTCH.52
 ffffffff821371c0 0000000000000024 d CSWTCH.523
@@ -27125,7 +27125,7 @@
 ffffffff82139680 0000000000000058 d CSWTCH.72
 ffffffff82139620 0000000000000048 d CSWTCH.74
 ffffffff8213c740 0000000000000020 d CSWTCH.74
-ffffffff821f04a0 0000000000000018 d CSWTCH.753
+ffffffff821f04a0 0000000000000018 d CSWTCH.766
 ffffffff8200e4e0 0000000000000020 d CSWTCH.77
 ffffffff821bffc0 0000000000000018 d CSWTCH.78
 ffffffff8200e4c0 0000000000000020 d CSWTCH.79
1|android_x86:/ #

2022-10-21 2:14 GMT+08:00, Alexander Potapenko <glider@google.com>:
> On Wed, Oct 19, 2022 at 2:37 PM 'Marco Elver' via kasan-dev <
> kasan-dev@googlegroups.com> wrote:
>
>> On Thu, Oct 20, 2022 at 04:07AM +0800, youling 257 wrote:
>> > That is i did,i already test, remove "u64 __tmp…kmsan_unpoison_memory",
>> no help.
>> > i only remove kmsan_copy_to_user, fix my issue.
>>
>> Ok - does only the below work (without the reverts)?
>>
>> diff --git a/include/linux/kmsan-checks.h b/include/linux/kmsan-checks.h
>> index c4cae333deec..eb05caa8f523 100644
>> --- a/include/linux/kmsan-checks.h
>> +++ b/include/linux/kmsan-checks.h
>> @@ -73,8 +73,8 @@ static inline void kmsan_unpoison_memory(const void
>> *address, size_t size)
>>  static inline void kmsan_check_memory(const void *address, size_t size)
>>  {
>>  }
>> -static inline void kmsan_copy_to_user(void __user *to, const void *from,
>> -                                     size_t to_copy, size_t left)
>> +static __always_inline void kmsan_copy_to_user(void __user *to, const
>> void *from,
>> +                                              size_t to_copy, size_t
>> left)
>>  {
>>  }
>>
>>
>> ... because when you say only removing kmsan_copy_to_user() (from
>> instrument_put_user()) works, it really doesn't make any sense. The only
>> explanation would be if the compiler inlining is broken.
>>
>>
> If what Marco suggests does not help, could you post the output of `nm -S
> vmlinux` with and without your revert so that we can see which functions
> were affected by the change?
>
> Unfortunately the top results are of no help, do you have the `perf` tool
> available in your system?
>
>
>> --
>> You received this message because you are subscribed to the Google Groups
>> "kasan-dev" group.
>> To unsubscribe from this group and stop receiving emails from it, send an
>> email to kasan-dev+unsubscribe@googlegroups.com.
>> To view this discussion on the web visit
>> https://groups.google.com/d/msgid/kasan-dev/Y1Bt%2BIa93mVV/lT3%40elver.google.com
>> .
>>
>
>
> --
> Alexander Potapenko
> Software Engineer
>
> Google Germany GmbH
> Erika-Mann-Straße, 33
> 80636 München
>
> Geschäftsführer: Paul Manicle, Liana Sebastian
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>

  parent reply	other threads:[~2022-10-21  5:55 UTC|newest]

Thread overview: 61+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-09-15 15:03 [PATCH v7 00/43] Add KernelMemorySanitizer infrastructure Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 01/43] x86: add missing include to sparsemem.h Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 02/43] stackdepot: reserve 5 extra bits in depot_stack_handle_t Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 03/43] instrumented.h: allow instrumenting both sides of copy_from_user() Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 04/43] x86: asm: instrument usercopy in get_user() and put_user() Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 05/43] asm-generic: instrument usercopy in cacheflush.h Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 06/43] kmsan: add ReST documentation Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 07/43] kmsan: introduce __no_sanitize_memory and __no_kmsan_checks Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 08/43] kmsan: mark noinstr as __no_sanitize_memory Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 09/43] x86: kmsan: pgtable: reduce vmalloc space Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 10/43] libnvdimm/pfn_dev: increase MAX_STRUCT_PAGE_SIZE Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 11/43] kmsan: add KMSAN runtime core Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 12/43] kmsan: disable instrumentation of unsupported common kernel code Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 13/43] MAINTAINERS: add entry for KMSAN Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 14/43] mm: kmsan: maintain KMSAN metadata for page operations Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 15/43] mm: kmsan: call KMSAN hooks from SLUB code Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 16/43] kmsan: handle task creation and exiting Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 17/43] init: kmsan: call KMSAN initialization routines Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 18/43] instrumented.h: add KMSAN support Alexander Potapenko
     [not found]   ` <20221019173620.10167-1-youling257@gmail.com>
     [not found]     ` <CAOzgRda_CToTVicwxx86E7YcuhDTcayJR=iQtWQ3jECLLhHzcg@mail.gmail.com>
2022-10-19 17:58       ` Marco Elver
2022-10-19 19:29         ` youling 257
2022-10-19 20:00           ` Marco Elver
2022-10-19 20:07             ` youling 257
2022-10-19 21:36               ` Marco Elver
     [not found]                 ` <CAG_fn=WLRN=C1rKrpq4=d=AO9dBaGxoa6YsG7+KrqAck5Bty0Q@mail.gmail.com>
2022-10-21  5:55                   ` youling 257 [this message]
2022-10-21  6:16                     ` Marco Elver
2022-10-21  6:39                       ` youling 257
2022-10-21  7:37                         ` Marco Elver
2022-10-21 15:19                           ` youling 257
     [not found]                             ` <CAG_fn=VE4qrXhLzEkNR_8PcO9N4AYYhNaXYvZNffvVEo7AHr-A@mail.gmail.com>
2022-10-21 17:21                               ` Kees Cook
     [not found]                             ` <CAG_fn=UVARRueXn4mU51TkzLTpZ=2fKNL7NAB3YH7mGP71ZhUQ@mail.gmail.com>
2022-10-22  6:24                               ` youling 257
2022-10-19 21:44               ` Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 19/43] kmsan: add iomap support Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 20/43] Input: libps2: mark data received in __ps2_command() as initialized Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 21/43] dma: kmsan: unpoison DMA mappings Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 22/43] virtio: kmsan: check/unpoison scatterlist in vring_map_one_sg() Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 23/43] kmsan: handle memory sent to/from USB Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 24/43] kmsan: add tests for KMSAN Alexander Potapenko
2022-09-15 15:03 ` [PATCH v7 25/43] kmsan: disable strscpy() optimization under KMSAN Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 26/43] crypto: kmsan: disable accelerated configs " Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 27/43] kmsan: disable physical page merging in biovec Alexander Potapenko
2022-09-15 20:58   ` Andrew Morton
2022-09-16  9:12     ` Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 28/43] block: kmsan: skip bio block merging logic for KMSAN Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 29/43] kcov: kmsan: unpoison area->list in kcov_remote_area_put() Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 30/43] security: kmsan: fix interoperability with auto-initialization Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 31/43] objtool: kmsan: list KMSAN API functions as uaccess-safe Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 32/43] x86: kmsan: disable instrumentation of unsupported code Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 33/43] x86: kmsan: skip shadow checks in __switch_to() Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 34/43] x86: kmsan: handle open-coded assembly in lib/iomem.c Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 35/43] x86: kmsan: use __msan_ string functions where possible Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 36/43] x86: kmsan: sync metadata pages on page fault Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 37/43] x86: kasan: kmsan: support CONFIG_GENERIC_CSUM on x86, enable it for KASAN/KMSAN Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 38/43] x86: fs: kmsan: disable CONFIG_DCACHE_WORD_ACCESS Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 39/43] x86: kmsan: don't instrument stack walking functions Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 40/43] entry: kmsan: introduce kmsan_unpoison_entry_regs() Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 41/43] bpf: kmsan: initialize BPF registers with zeroes Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 42/43] mm: fs: initialize fsdata passed to write_begin/write_end interface Alexander Potapenko
2022-09-15 15:04 ` [PATCH v7 43/43] x86: kmsan: enable KMSAN builds for x86 Alexander Potapenko
2022-09-15 21:05 ` [PATCH v7 00/43] Add KernelMemorySanitizer infrastructure Andrew Morton
2022-09-15 21:07   ` Andrew Morton

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