From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 4108922332E; Thu, 21 May 2026 13:26:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779369967; cv=none; b=KFdyqooOTVdl50Z/rwuv6y8pLASOo44MoS9KyD7WlMilbzkk0QrnBBoEhWvHx2tnIjNgaSLimz2k7xllKSNUwHBjc0lx+r5XwMktL2rdGmQOV/vwpdTOTWKt8V7CebYOGNPZRIgVdHB0S/+epEzN5lqSxHRpfGrpzq3EE3ztThE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779369967; c=relaxed/simple; bh=+nskVXn8YLsgST26DpsnpviZUK32fjLrbIjZaq9dKAI=; h=Content-Type:MIME-Version:Message-Id:In-Reply-To:References: Subject:From:To:Cc:Date; b=Y9KMMF6sk78lZauIPsykwFmgJutocCVK4FnQoDIdrJEu6JK3BVv4hjiLagKuZ4ZfqoHK4Cw1xYIP5VPAtwiURHUwZ1sTABk+EYBtvdEr7WtfTRPJYHGY7iSdEZiY6QN5Lbu+1uSvNf2WsklylQYuihAGa+BpwlZdEf+MetFIsbw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=gkxOPmTW; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="gkxOPmTW" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B87CE1F000E9; Thu, 21 May 2026 13:26:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1779369965; bh=udnhbms2AZ6NF1KnnCgVQc1JF3BU+KgaJGAulBs6Bsc=; h=In-Reply-To:References:Subject:From:To:Cc:Date; b=gkxOPmTW+0/4X+RsxEICBCj7J7Zc62fDhxdp2yzX/Hs/Y0kPygY1EwqCKu25QFr9F R8/60yIxOjiGRmz3ZaHb9davlK6RLCHCdneGRlqLUDRSRC+sz3jAwcTd3CtWpCyROo CtNJ7pta7iGVgdykd2J3SmRKZxk+LvGBdKw4rXUHd53ti8DKZ8+SEFgGq9OVY2QVXo kDWad06HIu/5E+sE6B/mRlIZq8XW0ZtmSR/BRj8ufKd9mVn38e1y1NVkoB0yIrut39 fmojIT/RFRk7WY8m4mhOki5ckypWc7YyEp57R9E+V6jeFfzPXwOPPyh+RvO3OEmuOe 8u/TWb1kcYIpQ== Content-Type: multipart/mixed; boundary="===============2532556505416087578==" Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <09bc3983509b9b4f7c115d5ad6369831e76ecc130950221e497fe5dc4686de5b@mail.kernel.org> In-Reply-To: <20260521124411.31133-9-jolsa@kernel.org> References: <20260521124411.31133-9-jolsa@kernel.org> Subject: Re: [PATCHv3 08/12] selftests/bpf: Change uprobe syscall tests to use nop10 From: bot+bpf-ci@kernel.org To: jolsa@kernel.org,oleg@redhat.com,peterz@infradead.org,mingo@kernel.org,mhiramat@kernel.org,andrii@kernel.org Cc: bpf@vger.kernel.org,linux-trace-kernel@vger.kernel.org,ast@kernel.org,andrii@kernel.org,daniel@iogearbox.net,martin.lau@kernel.org,eddyz87@gmail.com,yonghong.song@linux.dev,clm@meta.com,ihor.solodrai@linux.dev Date: Thu, 21 May 2026 13:26:05 +0000 (UTC) --===============2532556505416087578== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit > diff --git a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c > index c944136252c6..9653fb5608f2 100644 > --- a/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c > +++ b/tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c [ ... ] > @@ -388,14 +388,15 @@ static int find_uprobes_trampoline(void *tramp_addr) > return ret; > } > > -static unsigned char nop5[5] = { 0x0f, 0x1f, 0x44, 0x00, 0x00 }; > +static unsigned char nop10[10] = { 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 }; > +static unsigned char lea_rsp[5] = { 0x48, 0x8d, 0x64, 0x24, 0x80 }; > > -static void *find_nop5(void *fn) > +static void *find_nop10(void *fn) > { > int i; > > - for (i = 0; i < 10; i++) { > - if (!memcmp(nop5, fn + i, 5)) > + for (i = 0; i < 128; i++) { > + if (!memcmp(nop10, fn + i, 10)) > return fn + i; > } > return NULL; [ ... ] > @@ -432,7 +434,7 @@ static void check_detach(void *addr, void *tramp) > { > /* [uprobes_trampoline] stays after detach */ > ASSERT_OK(find_uprobes_trampoline(tramp), "uprobes_trampoline"); > - ASSERT_OK(memcmp(addr, nop5, 5), "nop5"); > + ASSERT_OK(memcmp(addr, jmp2B, 2), "jmp2B"); > } Is jmp2B declared somewhere? The identifier is used in memcmp() but does not appear to be defined anywhere in the file or included headers. A subsequent commit later in the series replaces this with a properly declared nop10_prefix array, confirming this is likely a missing definition. The pre-patch code referenced the defined static array nop5, but the new code references an undeclared symbol that will cause a compilation error. > diff --git a/tools/testing/selftests/bpf/prog_tests/usdt.c b/tools/testing/selftests/bpf/prog_tests/usdt.c > index 69759b27794d..fda3a298ccfc 100644 > --- a/tools/testing/selftests/bpf/prog_tests/usdt.c > +++ b/tools/testing/selftests/bpf/prog_tests/usdt.c > @@ -252,7 +252,7 @@ extern void usdt_1(void); > extern void usdt_2(void); > > static unsigned char nop1[1] = { 0x90 }; > -static unsigned char nop1_nop5_combo[6] = { 0x90, 0x0f, 0x1f, 0x44, 0x00, 0x00 }; > +static unsigned char nop1_nop10_combo[11] = { 0x90, 0x66, 0x2e, 0x0f, 0x1f, 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 }; > > static void *find_instr(void *fn, unsigned char *instr, size_t cnt) > { > int i; > > for (i = 0; i < 10; i++) { > if (!memcmp(instr, fn + i, cnt)) > return fn + i; > } > return NULL; > } Is the loop in find_instr() adequate to find this instruction sequence? In uprobe_syscall.c, find_nop10() was updated to search up to 128 bytes to account for compiler-generated prologues: tools/testing/selftests/bpf/prog_tests/uprobe_syscall.c:find_nop10() { for (i = 0; i < 128; i++) { if (!memcmp(nop10, fn + i, 10)) return fn + i; } } If a modern compiler generates a prologue longer than 9 bytes for usdt_2(), find_instr() will prematurely terminate and cause the subtest_optimized_attach() test to fail. This was acknowledged in v2 review with "yea find_instr needs same update, will fix" but remains unchanged. [ ... ] --- AI reviewed your patch. Please fix the bug or email reply why it's not a bug. See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md CI run summary: https://github.com/kernel-patches/bpf/actions/runs/26227520868 --===============2532556505416087578==--