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 B1BAD3624A4; Wed, 3 Dec 2025 16:52:39 +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=1764780759; cv=none; b=KsK+WkYRvkO9W7OSjWYo+3fLKD9Nrps6TPyLLvXtPuEAkPPUxaY1nvs6dW89/vIDn7dvj1p84YxpNj8lK/Gaq0DiVCHbO/ts3bP+c9FkkWD1qB2J06nhl05Q9YQZAlpnId8cIHnQKAcZwQzIMt6xwxheOJNRG61i1CEd7t52LOo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764780759; c=relaxed/simple; bh=T/nQUIYnU7LFnUI09xtxulyMyLNZA9FtRRJF6fb5KOg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Em05ZgZi+CpwBjp597lr4OhAuU0Lo/YkF5oSYt3mOVx5Nb/FckmNXw3cNy8eGI1BbJeqwHbtY5ul1sAWZXUT/nb83loN4K+leWAeirJQ2yE46BTjKsBCv1raCD0989d4HnU1/iCP0+AVPYPqd402q0Jbemr9oraYVRod+c5M4E8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=imhWkmNp; 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="imhWkmNp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2576CC4CEF5; Wed, 3 Dec 2025 16:52:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1764780759; bh=T/nQUIYnU7LFnUI09xtxulyMyLNZA9FtRRJF6fb5KOg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=imhWkmNpwGMQ98vBYCnnAYfx22jwVko/76P7O3TV+3ugEsE286XtpqPuZ6K07RLI+ Js3WS89Z3c2xLM1ZUuRGzjmjqczcNc9cZuBQWn9AimIj+Pl6SV3hKwte960tsW10Na 01G0Bx2Nd9IOWwiG4coUr+3paUAoJE9/S+3NHKmI= 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 6.12 064/132] MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow Date: Wed, 3 Dec 2025 16:29:03 +0100 Message-ID: <20251203152345.668510869@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251203152343.285859633@linuxfoundation.org> References: <20251203152343.285859633@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 6.12-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(-) diff --git a/arch/mips/mm/tlb-r4k.c b/arch/mips/mm/tlb-r4k.c index 3facf7cc6c7d..44a662536148 100644 --- 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 @@ -522,17 +523,26 @@ static int r4k_vpn_cmp(const void *a, const void *b) * 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++) { @@ -585,6 +595,10 @@ 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); } /* -- 2.52.0