From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AB238F589B2 for ; Thu, 23 Apr 2026 12:42:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=I2iUOz06N9pWMf1bIo71EnFA9O21Frf4P70pvQqdric=; b=TmFzm2+4nJY8Z8q/gNF17KsEzv c5uR2diJsIOoQozOmZvUJh4sP3i3YXuOpcGuL7zPVX+v5L9Nm5mfFiHsJIHLtv1atNGM4g5PLWkzH qXREtFFdMw+XOlVTTBnhs8CBsab9mfn9rpf70va6XhlwF42s//8TLv7cyPbHI79BVTusZ7SeF8AIj VSxYhL0AYYrg2SyjBuOWie5rAZSt0cqxwTKhrGQ6p06Kw6/Esh+TyzR9UXrymAEzo/xtr2t6glSDB 5L0LuMpN9ZZIIbBMt791XxBXJ6B7e481Sr+ZqG6cA79jp6nfpknKghSF45DWr/mgaHXIC7xBZY5Pp qCNIuBFA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wFtO3-0000000BdTj-3I8Q; Thu, 23 Apr 2026 12:42:31 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wFtNy-0000000BdRx-3uGg; Thu, 23 Apr 2026 12:42:29 +0000 Received: from CPC-namja-026ON.redmond.corp.microsoft.com (unknown [4.213.232.18]) by linux.microsoft.com (Postfix) with ESMTPSA id 2833120B7168; Thu, 23 Apr 2026 05:42:18 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 2833120B7168 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1776948146; bh=I2iUOz06N9pWMf1bIo71EnFA9O21Frf4P70pvQqdric=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=sdJr3BxSKfa5DEwVFAHUFBYZT3CYc4MAfq8UWukagegS/A86yvkIHkLGL8iNV/AmX sZQvA8TInk618z9cr/L8VcWhIK1vnpLV8JbFypwHHhnWweLdVlRRK6x4v0dVdtqL1i 5HUfRb7io3Hlx8KeTctmRzzkcsl9Mi34N8U1zmHM= From: Naman Jain To: "K . Y . Srinivasan" , Haiyang Zhang , Wei Liu , Dexuan Cui , Long Li , Catalin Marinas , Will Deacon , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Arnd Bergmann , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Michael Kelley Cc: Marc Zyngier , Timothy Hayes , Lorenzo Pieralisi , Sascha Bischoff , mrigendrachaubey , Naman Jain , linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-riscv@lists.infradead.org, vdso@mailbox.org, ssengar@linux.microsoft.com Subject: [PATCH v2 01/15] arm64: smp: Export arch_smp_send_reschedule for mshv_vtl module Date: Thu, 23 Apr 2026 12:41:51 +0000 Message-ID: <20260423124206.2410879-2-namjain@linux.microsoft.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20260423124206.2410879-1-namjain@linux.microsoft.com> References: <20260423124206.2410879-1-namjain@linux.microsoft.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260423_054227_016053_AAEFDE68 X-CRM114-Status: GOOD ( 10.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org mshv_vtl_main.c calls smp_send_reschedule() which expands to arch_smp_send_reschedule(). When CONFIG_MSHV_VTL=m, the module cannot access this symbol since it is not exported on arm64. smp_send_reschedule() is used in mshv_vtl_cancel() to interrupt a vCPU thread running on another CPU. When a vCPU is looping in mshv_vtl_ioctl_return_to_lower_vtl(), it checks a per-CPU cancel flag before each VTL0 entry. Setting cancel=1 alone is not enough if the target CPU thread is sleeping - the IPI from smp_send_reschedule() kicks the remote CPU out of idle/sleep so it re-checks the cancel flag and exits the loop promptly. Other architectures (riscv, loongarch, powerpc) already export this symbol. Add the same EXPORT_SYMBOL_GPL for arm64. This is required for adding arm64 support in MSHV_VTL. Reviewed-by: Michael Kelley Reviewed-by: Roman Kisel Signed-off-by: Naman Jain --- arch/arm64/kernel/smp.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 1aa324104afb..26b1a4456ceb 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -1152,6 +1152,7 @@ void arch_smp_send_reschedule(int cpu) { smp_cross_call(cpumask_of(cpu), IPI_RESCHEDULE); } +EXPORT_SYMBOL_GPL(arch_smp_send_reschedule); #ifdef CONFIG_ARM64_ACPI_PARKING_PROTOCOL void arch_send_wakeup_ipi(unsigned int cpu) -- 2.43.0