From nobody Mon Jul 21 17:05:19 2025 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4bm6GT0drlz62snP; Mon, 21 Jul 2025 17:05:21 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "R11" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4bm6GS4S7vz3SgQ; Mon, 21 Jul 2025 17:05:20 +0000 (UTC) (envelope-from jhb@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1753117520; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=G5j32OQqivY2D3Bfgag5Si0RVszcYGi+IJ0S8wfFV+k=; b=EEPLbCXPnSYMc44pV9naCDYxC5XayNMe50HiV8mVMeOkZAqVKwV0qf+t6rXAt5TRtWAVe7 mZ5c3ttrZO5LdXV9iDyqkQAIak725YJLIXSPoqJH1DcmncT1jV0L9TATVwWWh32+pgIH+j I7fgnq0bR6Z2HxeMpCfW1pcQ7v+LO1KNVMVmc4tuI1R3krvPZlUK4KrIeVOzjNX4Quj7N5 nyPjT+4hVTg07CTqEN0Je7szfD+7rg758rrbKjIdxHXX8BBOas2hEkSRbwQx2mnuiE5qCh lbUj00gLqw2rJwBT3UxMO5qLIdAlWY/DDSK/mSDXQSJNRP+VIx3l96igeOVDJw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1753117520; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=G5j32OQqivY2D3Bfgag5Si0RVszcYGi+IJ0S8wfFV+k=; b=G0/N1SqGjD74IztKPsKBk4XibXBLGiC/ptCQ7BdCo/w31CF+/VoXTdtDO6vg1JHv58UE4V dynYeWiL+nX7NBKbici58PyDbMmJRPzMBCqtIWZqjCw4TbQwo1jFNRqdm6YS8BOBLml6fi USPysi1lmRM55pXdAnZDQfmhH090WVeF5/GJPXSYVmTAnKXjFLSBKCZpuRtcEGwJo/Ft3X Uq1qthBpvzQdetHP1QUCAnqEm9p645xysaXpbRe1Bxt4oqfjCb7r7Hf2GrO0I9jyO7RM/x 8sgZe+Pdhcl7ORzfoqnHSWAy+hNq9NkMtvVgRpPRtY1AhnpFgSAnMrfkSvDJYw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1753117520; a=rsa-sha256; cv=none; b=b2diOntCEnstCNHR3Z0pDBMGaPTmlvZGRaoPYttVLifIH6mMz07hJoXCYXRhO4R0zzBcrS hjUTcPWKSJP4AUhxsv9/HV7mPy8d/zvvQg0STmm/akBtgnpavJiAnT30UhbleydwyGvHXt NqCcc3EV4R6yNAbe/KydsUWHXwQ3jt1YwAn3UOOAVHFQyv3NJ/lfFnUXbv2U2eoWrEi5mG MStHqCCkFq+7UtfPzGryRk7VoP8x0+ylebzs4wHoNgk/CdluBYMfBBWN2iwcB7WSbLxUSc doRd9yKV1/8z6PrjUdcu7Zfr5k6vhhVIZ0LL+wCRXRlSS7hYeknjQETstlKFbA== Received: from [IPV6:2601:5c0:4200:b830:5995:2e3f:98fd:7c0c] (unknown [IPv6:2601:5c0:4200:b830:5995:2e3f:98fd:7c0c]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (Client did not present a certificate) (Authenticated sender: jhb) by smtp.freebsd.org (Postfix) with ESMTPSA id 4bm6GS2P0HzGby; Mon, 21 Jul 2025 17:05:20 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Message-ID: <027a49e1-dbcb-4b2b-ae8a-938616f43cf2@FreeBSD.org> Date: Mon, 21 Jul 2025 13:05:19 -0400 List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@FreeBSD.org MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: git: cc21f6e53f43 - main - amd64: Make a comment less confusing Content-Language: en-US To: Mark Johnston Cc: src-committers@freebsd.org, dev-commits-src-all@freebsd.org, dev-commits-src-main@freebsd.org References: <202507211458.56LEwD36053783@gitrepo.freebsd.org> <35003f37-9e55-4a92-ae6e-58b35409700b@FreeBSD.org> From: John Baldwin In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 7/21/25 12:43, Mark Johnston wrote: > On Mon, Jul 21, 2025 at 12:37:23PM -0400, John Baldwin wrote: >> On 7/21/25 10:58, Mark Johnston wrote: >>> The branch main has been updated by markj: >>> >>> URL: https://cgit.FreeBSD.org/src/commit/?id=cc21f6e53f43f0e4c082222460d90ea581f3e2d6 >>> >>> commit cc21f6e53f43f0e4c082222460d90ea581f3e2d6 >>> Author: Mark Johnston >>> AuthorDate: 2025-07-21 13:33:31 +0000 >>> Commit: Mark Johnston >>> CommitDate: 2025-07-21 14:57:58 +0000 >>> >>> amd64: Make a comment less confusing >>> Also merge two printf()s. No functional change intended. >>> Reviewed by: kib >>> MFC after: 1 week >>> Differential Revision: https://reviews.freebsd.org/D51452 >>> --- >>> sys/amd64/amd64/trap.c | 13 ++++++------- >>> 1 file changed, 6 insertions(+), 7 deletions(-) >>> >>> diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c >>> index d9a5f7096a6e..f3469ed5e2bc 100644 >>> --- a/sys/amd64/amd64/trap.c >>> +++ b/sys/amd64/amd64/trap.c >>> @@ -37,7 +37,6 @@ >>> * SUCH DAMAGE. >>> */ >>> -#include >>> /* >>> * AMD64 Trap and System call handling >>> */ >>> @@ -898,9 +897,9 @@ trap_diag(struct trapframe *frame, vm_offset_t eva) >>> printf("\n\nFatal trap %d: %s while in %s mode\n", type, >>> type < nitems(trap_msg) ? trap_msg[type] : UNKNOWN, >>> TRAPF_USERMODE(frame) ? "user" : "kernel"); >>> - /* two separate prints in case of a trap on an unmapped page */ >>> - printf("cpuid = %d; ", PCPU_GET(cpuid)); >>> - printf("apic id = %02x\n", PCPU_GET(apic_id)); >>> + /* Print these separately in case pcpu accesses trap. */ >>> + printf("cpuid = %d; apic id = %02x\n", PCPU_GET(cpuid), >>> + PCPU_GET(apic_id)); >>> if (type == T_PAGEFLT) { >>> printf("fault virtual address = 0x%lx\n", eva); >>> printf("fault code = %s %s %s%s%s, %s\n", >>> @@ -1021,9 +1020,9 @@ dblfault_handler(struct trapframe *frame) >>> frame->tf_cs, frame->tf_ss, frame->tf_ds, frame->tf_es, >>> frame->tf_fs, frame->tf_gs, >>> rdmsr(MSR_FSBASE), rdmsr(MSR_GSBASE), rdmsr(MSR_KGSBASE)); >>> - /* two separate prints in case of a trap on an unmapped page */ >>> - printf("cpuid = %d; ", PCPU_GET(cpuid)); >>> - printf("apic id = %02x\n", PCPU_GET(apic_id)); >>> + /* Print these separately in case pcpu accesses trap. */ >>> + printf("cpuid = %d; apic id = %02x\n", PCPU_GET(cpuid), >>> + PCPU_GET(apic_id)); >>> panic("double fault"); >> >> Eh, if any of the accesses fault you don't get any of the printf, > > Right, but I believe the comment is referring to the preceding printf, > which doesn't print any PCPU fields. In what situation would > PCPU_GET(apic_id) fault while PCPU_GET(cpuid) succeeds? > > (Yes, my commit message here should have been better.) Oh, woof. The second printf used to read from the lapic directly instead of per-CPU data. I changed it here: https://svnweb.freebsd.org/base?view=revision&revision=121986 So prior to that each printf was indeed reading from separate pages: #ifdef SMP /* two separate prints in case of a trap on an unmapped page */ printf("cpuid = %d; ", PCPU_GET(cpuid)); printf("lapic.id = %08x\n", lapic.id); #endif The comment used to reference _three_ printfs prior to the SMPng commit: https://svnweb.freebsd.org/base/head/sys/i386/i386/trap.c?r1=65556&r2=65557& The original comment (referencing 3) was added by peter@ here: https://svnweb.freebsd.org/base?view=revision&revision=29128 It certainly seems to only apply to the printfs under #ifdef SMP. Removing the comment has the additional property of fixing the style bug of not having a blank line before the comment that was previously provided by the #ifdef SMP. :) -- John Baldwin