From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=91.218.175.15 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792516546; b=fqi/1VnQo9hDvVYJ332OYpjjXdWnyzOSmIh1Y/FitOYAcPSpRi7qgJDH3FjgZfYZQwAo FJBbkC6uPJ6kOoLvnc/lb82PYkPko2oGmQy1QUFQzHPZNyFu7/gXiJgAuJ2rbOz/6dKJN lhYzvmVMt/+64+FB5oW8CP+v92VOEUILLClF/Tre/eFn/kJzQuOyDDfv0hwXw1r5iw80S sMAkXDgrwsMG4si/w07JIUhdSbmF+/rYKhPkot3uVaXCDYp27E1Z4xOx7xsKvB1P9fLwx Rx05wMxZtWWAaLpJ4W5aoiIziag4Qz53a+d8xVF0ZD3gCc+SfGaC7Kq+FTf4Up/ExCA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792516546; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Message-ID:Date:MIME-Version:User-Agent: Subject:To:Cc:References:From:Content-Language:In-Reply-To: Content-Type:Content-Transfer-Encoding; bh=yoZ0s+1JjaWMxbOAdwnEZHjXlxQoadj0CaIfiBABUd0=; b=4Z02ZD0FkLZ0Xf67Zt8w+uyyITR27rKl3exy3iHnO5ScZoztQisTictsKK6eXyqPTtNV T32qqYVOGrkrW0Bilkr8Wm3xcMFB8HwG7pAScQjaRsiOEhComHmiT3Rf+7dVFe98aaE5s Y158FdSvB1HYBXRE26d0Sjgrg9eFe5m/KavUkscR1qAnf+i5M3+bLdfwJ4fS0HucaJYLs hbPiWXqgo71o7mQ8JtcH7bviQlQboZumgqCBXVC+E4HnkXwkK40PNS9dg57iZWmptbzpE 2n8Ikd1ZeVWlL4quHPd0nc4XmP7gbQKuj0NOoZDapQNubehCqCtd4ejmcYyNo1sbPJQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b="GbjCIC/d"; arc=none smtp.remote-ip=91.218.175.15 Received: from mta0.migadu.com (out-15.mta0.migadu.com [91.218.175.15]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7D473606A32F for ; Tue, 20 Oct 2026 17:15:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 7D473606A32F Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=GbjCIC/d X-Envelope-To: bpf@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=+MYMcLaKmflZhPpa6ORxIVfcC9BERtwH9CFho9USxWA=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792516543; v=1; x=1793121343; b=GbjCIC/d8loIPSoDHfOexvnlL8QBLPP1IKfsilURfcM5bnYnH4fwCM7t7LNVUoVlcJ4p8Rrt wSJf3ieipMIHwtOsj/ZUKxXm9u94vE5xA99RHYpogVFnEcr/OUaSWXur0+8MdOnAqvuVK5xrszl TFVBpT0fhP9ZPNSTwBoFHzL8= X-Envelope-To: bpf@vger.kernel.org Received: by smtp.migadu.com with ESMTPS id a6299d0d0a6e04fa; Tue, 20 Oct 2026 17:15:42 +0000 X-Mizu-Trace-ID: a6299d0d0a6e04fa X-Migadu-Flow: FLOW_OUT Message-ID: <9f4fb200-9ec6-42de-8f9f-5eac10f258d7@linux.dev> Date: Tue, 20 Oct 2026 10:15:37 -0700 X-Mailing-List: bpf@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH bpf-next v3 10/12] selftests/bpf: Cover the low-32 link for narrowing stack fills To: sashiko-reviews@lists.linux.dev Cc: bpf@vger.kernel.org References: <20261020161907.2115379-1-vineet.gupta@linux.dev> <20261020161907.2115379-11-vineet.gupta@linux.dev> From: Vineet Gupta Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/20/26 9:29 AM, sashiko-bot@kernel.org wrote: > Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider: > - [Low] selftests/bpf: misplaced ifdef in sext_byte_fill_drops_sext_link() > -- > > commit 0f3b5c981ef84ecf43731c167adb9d7addf744eb > Author: Vineet Gupta > > selftests/bpf: Cover the low-32 link for narrowing stack fills > > This commit adds eight BPF verifier selftests covering low-32 scalar link > tracking across narrowing and sign-extending stack fills, and introduces a > CAN_USE_LDSX macro in bpf_misc.h to guard tests that use sign-extending > loads. > >> diff --git a/tools/testing/selftests/bpf/progs/verifier_linked_scalars.c b/tools/testing/selftests/bpf/progs/verifier_linked_scalars.c [snip...] >> +SEC("socket") >> +__success __log_level(2) >> +#ifdef CAN_USE_MOVSX >> +/* >> + * Needs MOVSX as well as LDSX: the BPF_REG_LINK_SEXT under test is built with >> + * r7 = (s32)r6, and only the byte fill below is an ldsx. >> + */ >> +/* a surviving link would print as R2=scalar(id=N+0.sx,smin=... */ >> +__msg("(91) r2 = *(s8 *)(r10 {{.*}} R2=scalar(smin=") >> +__naked void sext_byte_fill_drops_sext_link(void) >> +{ > [ ... ] >> +} >> +#endif /* CAN_USE_MOVSX */ >> + >> +#endif /* CAN_USE_LDSX */ >> + >> char _license[] SEC("license") = "GPL"; > [Severity: Low] > Should SEC("socket") and __success __log_level(2) on > sext_byte_fill_drops_sext_link() be placed inside the #ifdef CAN_USE_MOVSX > block? Indeed that bracketing came out weird. > In tools/testing/selftests/bpf/progs/bpf_misc.h, CAN_USE_LDSX and > CAN_USE_MOVSX can be enabled independently via __BPF_FEATURE_LDSX and > __BPF_FEATURE_MOVSX Independently meaning ? __BPF_FEATURE* are indeed compiler toggle derived but the CAN_USE* additionally reflect whether arch JITs support them so they are a combination of __BPF_FEATURE* and arch JIT support. > (for example, with bpf-gcc -mldsx/-msmov flags). Just for correctness, -mldsx doesn't exist for gcc, -msmov covers both. > If CAN_USE_LDSX is defined while CAN_USE_MOVSX is not defined, the body of > the #ifdef CAN_USE_MOVSX block is preprocessed out, leaving those attributes > dangling so they attach to the following _license declaration (or to any test > function added after this block). Indeed the attribute placement needs fixing. Thx, -Vineet