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 E573A393DDB; Wed, 3 Dec 2025 16:57:55 +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=1764781076; cv=none; b=UksDpHZN9QNfX/0kOD3mt2fgRHOVlVeFB7Wjf01rvj+hyRkZoWTJISAvyh1lWGsdgynBeVlhvIXhmTSlfRRGBfDmYQ23CV36FwUpZ56O3xWuXlrly+krCgPB49K+gRyPKW+N5dPiHsfPOdSq4l1oTtOt47MNwKosVeznPs39yuA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764781076; c=relaxed/simple; bh=aetw6ms5U3Rrkyao06Q+31RDIPQZ9qMZtWEmkyAvsVo=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=cegfvZhxSJzVYAEh085yQ5oXMiCl3oBOCzagtfmLJQx3ffGSn6TvFZyDwPOV0YdZarBRllRwJXDroCj/20lxSnkWKuuHDyaW+sY2BJsNzImsAlTmSHkMnRXx8odDOSGkdkYCE3DGIsGMQ3R4/ZCOIqvDHUasSu/Qb1nvCJ9FUa8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OoULEohx; 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="OoULEohx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 42927C4CEF5; Wed, 3 Dec 2025 16:57:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1764781075; bh=aetw6ms5U3Rrkyao06Q+31RDIPQZ9qMZtWEmkyAvsVo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OoULEohxgQ5CUofktULoTc0T9Zjl80W//XUrgepf3L5FdKPlpPLn9PRPpsOSLQuBC hgdaJYW9+pkXga9lLU2z5NTFe90mgWZ5wOvCjAUsOknmVg4TbC/+D/bhHcOFxnlytU rQApCQ7yCJoucsm3PxQvMwTINfCyT2+2KK2DXy9A= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, "Maciej W. Rozycki" , Gregory CLEMENT , Klara Modin , Thomas Bogendoerfer Subject: [PATCH 6.6 41/93] MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow Date: Wed, 3 Dec 2025 16:29:34 +0100 Message-ID: <20251203152338.038542298@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251203152336.494201426@linuxfoundation.org> References: <20251203152336.494201426@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Thomas Bogendoerfer commit 841ecc979b18d3227fad5e2d6a1e6f92688776b5 upstream. Owing to Config4.MMUSizeExt and VTLB/FTLB MMU features later MIPSr2+ cores can have more than 64 TLB entries. Therefore allocate an array for uniquification instead of placing too an small array on the stack. Fixes: 35ad7e181541 ("MIPS: mm: tlb-r4k: Uniquify TLB entries on init") Co-developed-by: Maciej W. Rozycki Signed-off-by: Maciej W. Rozycki Cc: stable@vger.kernel.org # v6.17+: 9f048fa48740: MIPS: mm: Prevent a TLB shutdown on initial uniquification Cc: stable@vger.kernel.org # v6.17+ Tested-by: Gregory CLEMENT Tested-by: Klara Modin Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman --- arch/mips/mm/tlb-r4k.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) --- a/arch/mips/mm/tlb-r4k.c +++ b/arch/mips/mm/tlb-r4k.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -520,17 +521,26 @@ static int r4k_vpn_cmp(const void *a, co * Initialise all TLB entries with unique values that do not clash with * what we have been handed over and what we'll be using ourselves. */ -static void r4k_tlb_uniquify(void) +static void __ref r4k_tlb_uniquify(void) { - unsigned long tlb_vpns[1 << MIPS_CONF1_TLBS_SIZE]; int tlbsize = current_cpu_data.tlbsize; + bool use_slab = slab_is_available(); int start = num_wired_entries(); + phys_addr_t tlb_vpn_size; + unsigned long *tlb_vpns; unsigned long vpn_mask; int cnt, ent, idx, i; vpn_mask = GENMASK(cpu_vmbits - 1, 13); vpn_mask |= IS_ENABLED(CONFIG_64BIT) ? 3ULL << 62 : 1 << 31; + tlb_vpn_size = tlbsize * sizeof(*tlb_vpns); + tlb_vpns = (use_slab ? + kmalloc(tlb_vpn_size, GFP_KERNEL) : + memblock_alloc_raw(tlb_vpn_size, sizeof(*tlb_vpns))); + if (WARN_ON(!tlb_vpns)) + return; /* Pray local_flush_tlb_all() is good enough. */ + htw_stop(); for (i = start, cnt = 0; i < tlbsize; i++, cnt++) { @@ -583,6 +593,10 @@ static void r4k_tlb_uniquify(void) tlbw_use_hazard(); htw_start(); flush_micro_tlb(); + if (use_slab) + kfree(tlb_vpns); + else + memblock_free(tlb_vpns, tlb_vpn_size); } /*