From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 539EC2676CF for ; Mon, 28 Apr 2025 11:58:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745841483; cv=none; b=OZkmWmnhdBYaH95Nizy3hfkQs25zkXFRbj4sFngbclMcWfA5rKHN0auwCcuc+17+9x0+JtYnBC/pSUHSEOHR3PEBStpeR6RmjBMnKPlDQrdlVis/NTwBCD9iKpZQTu2tH/kJtldLIzNjBN9BdjtFAgDb94Jconj3Zmp/rggpJjw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745841483; c=relaxed/simple; bh=oL9rfbEgU13D4OBb0eEMhZXu9az9PBZkHKOVgo0RIAs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LPuJX9680PFKem1MibXQX7kkWoQkXS7TSPFyYV3GXGWElWHrpqUN1IUGmOwK50Wg14Ae61SfiYBXRH0MJIaffHz0xcHSRq8nMgIOWrygRUeOGaCEqHnuAF1Js6gyq2Cu9iV/8W7zV2M1LIsqUnYx3x6cX/TeSk+lUrqr5ZOOvXo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VrbAB3JU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="VrbAB3JU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3FA5FC4CEE4; Mon, 28 Apr 2025 11:58:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745841482; bh=oL9rfbEgU13D4OBb0eEMhZXu9az9PBZkHKOVgo0RIAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VrbAB3JUOEdZaDI79p73EPwgzx7QHWOy81orpTfosdd0hFVNb1rHTUnc7Q4IBlXaG Si54ET2xuSOC7H6hHan4LEa8OXVjYn5izRlqcXTKIQB+INuSCt2EWhBQA4X7eFuxyE icynasQl5Nx3bbvr9b5fklDWgAU4c3yfANI39Lkdsb/51Ok0FtjC/++SuIdyMUFAgA GXm5CBlcrDVJHNp+xF2zpEkRfgr1Ns0+ydgsQUZhKVlawpiT8tS1BBg9XMWbTCpFvW mBnuCcd9GKnyxGrvNKrEUEta84w/qI903THpVRQWB/a9Wfew1WK7D536g+EJ/RVrME ElV1M9IiISulw== From: "Aneesh Kumar K.V (Arm)" To: kvm@vger.kernel.org Cc: Suzuki K Poulose , Steven Price , Will Deacon , Julien Thierry , "Aneesh Kumar K.V (Arm)" , Alexandru Elisei Subject: [PATCH kvmtool v3 3/3] cpu: vmexit: Handle KVM_EXIT_UNKNOWN exit reason correctly Date: Mon, 28 Apr 2025 17:27:45 +0530 Message-ID: <20250428115745.70832-4-aneesh.kumar@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250428115745.70832-1-aneesh.kumar@kernel.org> References: <20250428115745.70832-1-aneesh.kumar@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit The return value for kernel VM exit handlers is confusing and has led to errors in different kernel exit handlers. A return value of 0 indicates a return to the VMM, whereas a return value of 1 indicates resuming execution in the guest. Some handlers mistakenly return 0 to force a return to the guest. This worked in kvmtool because the exit_reason defaulted to 0 (KVM_EXIT_UNKNOWN), and kvmtool did not error out on an unknown exit reason. However, forcing a VMM exit with error on KVM_EXIT_UNKNOWN exit_reson would help catch these bugs early. Reviewed-by: Alexandru Elisei Signed-off-by: Aneesh Kumar K.V (Arm) --- kvm-cpu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kvm-cpu.c b/kvm-cpu.c index 7abbdcebf075..a76dfee561ec 100644 --- a/kvm-cpu.c +++ b/kvm-cpu.c @@ -190,7 +190,7 @@ int kvm_cpu__start(struct kvm_cpu *cpu) switch (cpu->kvm_run->exit_reason) { case KVM_EXIT_UNKNOWN: - break; + goto panic_kvm; case KVM_EXIT_DEBUG: kvm_cpu__show_registers(cpu); kvm_cpu__show_code(cpu); -- 2.43.0