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 C7B633C6615 for ; Tue, 17 Mar 2026 12:58:44 +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=1773752324; cv=none; b=ESLahdVOCPClJBk9Kd82KdfU21hnmoQ4HdzWhitb4U89giBRiT7EmWFs9xw8sLhjS+HJtycygI5GDIjEajGjK2G9bFkHLg8TzH15RY/IQQLFrKudyaXp9c+SVPBfiNSMmQbbT2QHxVHFyypK5oYqh1Yi8bGitJA6/dWpIXd3b7w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773752324; c=relaxed/simple; bh=+PR1Vy0J+ulm2OQ/xFpmJ5lGFhyIHO7jOs3dtuQFs14=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=Q4xm9yWM6C7gBbE4m0n50JPSeplGpAIo8o31HYWODnNAUbhvY77J8QE6aLFoZRtleWzlsgBa7HlIxus6CVd8RAxv9opi626GZjAPHkB7TrfbLydsifO0++gjHapzjftrqxT3EjvZcGBuEkrhfl/tWC+ztrbvuRm1yz5veQnPwZk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=PowvjCfq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="PowvjCfq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C355EC4CEF7; Tue, 17 Mar 2026 12:58:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773752324; bh=+PR1Vy0J+ulm2OQ/xFpmJ5lGFhyIHO7jOs3dtuQFs14=; h=Subject:To:Cc:From:Date:From; b=PowvjCfqZxRGMSjuudVDO5QxPK/a41qDK/Y5Y8azD6v+HmnUQeAr1WOulOT5zbjiu eT+AKPghCO/RI2OQSrzQ3zLSdswoNyiZzOhACngDPXnScoYhDwx42KKNJpxlGpAvJg 6TxNhsilT86CJUTB6b4yVzAxbVhVHbYGto5CYBjo= Subject: FAILED: patch "[PATCH] powerpc64/bpf: do not increment tailcall count when prog is" failed to apply to 6.19-stable tree To: hbathini@linux.ibm.com,maddy@linux.ibm.com,venkat88@linux.ibm.com Cc: From: Date: Tue, 17 Mar 2026 13:58:40 +0100 Message-ID: <2026031740-avenging-arguably-7411@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.19.y git checkout FETCH_HEAD git cherry-pick -x 521bd39d9d28ce54cbfec7f9b89c94ad4fdb8350 # git commit -s git send-email --to '' --in-reply-to '2026031740-avenging-arguably-7411@gregkh' --subject-prefix 'PATCH 6.19.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 521bd39d9d28ce54cbfec7f9b89c94ad4fdb8350 Mon Sep 17 00:00:00 2001 From: Hari Bathini Date: Tue, 3 Mar 2026 23:40:25 +0530 Subject: [PATCH] powerpc64/bpf: do not increment tailcall count when prog is NULL Do not increment tailcall count, if tailcall did not succeed due to missing BPF program. Fixes: ce0761419fae ("powerpc/bpf: Implement support for tail calls") Cc: stable@vger.kernel.org Tested-by: Venkat Rao Bagalkote Signed-off-by: Hari Bathini Signed-off-by: Madhavan Srinivasan Link: https://patch.msgid.link/20260303181031.390073-2-hbathini@linux.ibm.com diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index b1a3945ccc9f..44ce8a8783f9 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -522,9 +522,30 @@ static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 o /* * tail_call_info++; <- Actual value of tcc here + * Writeback this updated value only if tailcall succeeds. */ EMIT(PPC_RAW_ADDI(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), 1)); + /* prog = array->ptrs[index]; */ + EMIT(PPC_RAW_MULI(bpf_to_ppc(TMP_REG_2), b2p_index, 8)); + EMIT(PPC_RAW_ADD(bpf_to_ppc(TMP_REG_2), bpf_to_ppc(TMP_REG_2), b2p_bpf_array)); + EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_2), bpf_to_ppc(TMP_REG_2), + offsetof(struct bpf_array, ptrs))); + + /* + * if (prog == NULL) + * goto out; + */ + EMIT(PPC_RAW_CMPLDI(bpf_to_ppc(TMP_REG_2), 0)); + PPC_BCC_SHORT(COND_EQ, out); + + /* goto *(prog->bpf_func + prologue_size); */ + EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_2), bpf_to_ppc(TMP_REG_2), + offsetof(struct bpf_prog, bpf_func))); + EMIT(PPC_RAW_ADDI(bpf_to_ppc(TMP_REG_2), bpf_to_ppc(TMP_REG_2), + FUNCTION_DESCR_SIZE + bpf_tailcall_prologue_size)); + EMIT(PPC_RAW_MTCTR(bpf_to_ppc(TMP_REG_2))); + /* * Before writing updated tail_call_info, distinguish if current frame * is storing a reference to tail_call_info or actual tcc value in @@ -539,24 +560,6 @@ static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 o /* Writeback updated value to tail_call_info */ EMIT(PPC_RAW_STD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_2), 0)); - /* prog = array->ptrs[index]; */ - EMIT(PPC_RAW_MULI(bpf_to_ppc(TMP_REG_1), b2p_index, 8)); - EMIT(PPC_RAW_ADD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), b2p_bpf_array)); - EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), offsetof(struct bpf_array, ptrs))); - - /* - * if (prog == NULL) - * goto out; - */ - EMIT(PPC_RAW_CMPLDI(bpf_to_ppc(TMP_REG_1), 0)); - PPC_BCC_SHORT(COND_EQ, out); - - /* goto *(prog->bpf_func + prologue_size); */ - EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), offsetof(struct bpf_prog, bpf_func))); - EMIT(PPC_RAW_ADDI(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), - FUNCTION_DESCR_SIZE + bpf_tailcall_prologue_size)); - EMIT(PPC_RAW_MTCTR(bpf_to_ppc(TMP_REG_1))); - /* tear down stack, restore NVRs, ... */ bpf_jit_emit_common_epilogue(image, ctx);