kernel: bump 6.18 to 6.18.23

Changelog: https://cdn.kernel.org/pub/linux/kernel/v6.x/ChangeLog-6.18.23

Removed upstreamed:
  generic/pending-6.18/360-Revert-MIPS-mm-kmalloc-tlb_vpn-array-to-avoid-stack-.patch[1,2]
  generic/pending-6.18/361-Revert-MIPS-mm-Prevent-a-TLB-shutdown-on-initial-uni.patch[3]

All other patches automatically rebased via update_kernel.sh

Upstream fixed booting the RealTek MIPS 4KEc SoCs. The reverts are not
needed any more.

1. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v6.18.23&id=ccc6a2241a49f68d8656ab1e10df377acfe2c5b4
2. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v6.18.23&id=6c600fc0e99180c7a1b91c93e359009be8b4cfc2
3. https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v6.18.23&id=d8b281165a86041bb40e055eb79f735826d0df1b

Build system: x86/64
Build-tested: x86/64-glibc
Run-tested: x86/64-glibc

Signed-off-by: John Audia <therealgraysky@proton.me>
Link: https://github.com/openwrt/openwrt/pull/22890
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>

target/linux/generic/kernel-6.18

@@ -1,2 +1,2 @@
-LINUX_VERSION-6.18 = .22
-LINUX_KERNEL_HASH-6.18.22 = a23c92faf3657385c2c6b5f4edd8f81b808907ebe603fa30699eae224da55f59
+LINUX_VERSION-6.18 = .23
+LINUX_KERNEL_HASH-6.18.23 = 2a2d8e76bfcd135ab861bb9795211574eeff6d4ede9cc920f7c137587e835134

target/linux/generic/pending-6.18/360-Revert-MIPS-mm-kmalloc-tlb_vpn-array-to-avoid-stack-.patch

@@ -1,60 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Hauke Mehrtens <hauke@hauke-m.de>
-Date: Mon, 15 Dec 2025 01:45:07 +0100
-Subject: Revert "MIPS: mm: kmalloc tlb_vpn array to avoid stack overflow"
-
-This reverts commit 63a93d1cd6077d79735f804f5a4957bfb240280c.
----
- arch/mips/mm/tlb-r4k.c | 18 ++----------------
- 1 file changed, 2 insertions(+), 16 deletions(-)
-
---- a/arch/mips/mm/tlb-r4k.c
-+++ b/arch/mips/mm/tlb-r4k.c
-@@ -12,7 +12,6 @@
- #include <linux/init.h>
- #include <linux/sched.h>
- #include <linux/smp.h>
--#include <linux/memblock.h>
- #include <linux/mm.h>
- #include <linux/hugetlb.h>
- #include <linux/export.h>
-@@ -523,26 +522,17 @@ 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 __ref r4k_tlb_uniquify(void)
-+static void 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_ATOMIC) :
--		    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++) {
-@@ -595,10 +585,6 @@ static void __ref 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);
- }
- 
- /*

target/linux/generic/pending-6.18/361-Revert-MIPS-mm-Prevent-a-TLB-shutdown-on-initial-uni.patch

@@ -1,146 +0,0 @@
-From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
-From: Hauke Mehrtens <hauke@hauke-m.de>
-Date: Mon, 15 Dec 2025 01:45:20 +0100
-Subject: Revert "MIPS: mm: Prevent a TLB shutdown on initial uniquification"
-
-This reverts commit 135178e90aa43ad949534e1d6e376c4034942caa.
----
- arch/mips/mm/tlb-r4k.c | 100 +++++++++++++++--------------------------
- 1 file changed, 37 insertions(+), 63 deletions(-)
-
---- a/arch/mips/mm/tlb-r4k.c
-+++ b/arch/mips/mm/tlb-r4k.c
-@@ -15,7 +15,6 @@
- #include <linux/mm.h>
- #include <linux/hugetlb.h>
- #include <linux/export.h>
--#include <linux/sort.h>
- 
- #include <asm/cpu.h>
- #include <asm/cpu-type.h>
-@@ -509,79 +508,55 @@ static int __init set_ntlb(char *str)
- 
- __setup("ntlb=", set_ntlb);
- 
--
--/* Comparison function for EntryHi VPN fields.  */
--static int r4k_vpn_cmp(const void *a, const void *b)
--{
--	long v = *(unsigned long *)a - *(unsigned long *)b;
--	int s = sizeof(long) > sizeof(int) ? sizeof(long) * 8 - 1: 0;
--	return s ? (v != 0) | v >> s : v;
--}
--
--/*
-- * 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.
-- */
-+/* Initialise all TLB entries with unique values */
- static void r4k_tlb_uniquify(void)
- {
--	unsigned long tlb_vpns[1 << MIPS_CONF1_TLBS_SIZE];
--	int tlbsize = current_cpu_data.tlbsize;
--	int start = num_wired_entries();
--	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;
-+	int entry = num_wired_entries();
- 
- 	htw_stop();
-+	write_c0_entrylo0(0);
-+	write_c0_entrylo1(0);
- 
--	for (i = start, cnt = 0; i < tlbsize; i++, cnt++) {
--		unsigned long vpn;
-+	while (entry < current_cpu_data.tlbsize) {
-+		unsigned long asid_mask = cpu_asid_mask(&current_cpu_data);
-+		unsigned long asid = 0;
-+		int idx;
- 
--		write_c0_index(i);
--		mtc0_tlbr_hazard();
--		tlb_read();
--		tlb_read_hazard();
--		vpn = read_c0_entryhi();
--		vpn &= vpn_mask & PAGE_MASK;
--		tlb_vpns[cnt] = vpn;
-+		/* Skip wired MMID to make ginvt_mmid work */
-+		if (cpu_has_mmid)
-+			asid = MMID_KERNEL_WIRED + 1;
- 
--		/* Prevent any large pages from overlapping regular ones.  */
--		write_c0_pagemask(read_c0_pagemask() & PM_DEFAULT_MASK);
-+		/* Check for match before using UNIQUE_ENTRYHI */
-+		do {
-+			if (cpu_has_mmid) {
-+				write_c0_memorymapid(asid);
-+				write_c0_entryhi(UNIQUE_ENTRYHI(entry));
-+			} else {
-+				write_c0_entryhi(UNIQUE_ENTRYHI(entry) | asid);
-+			}
-+			mtc0_tlbw_hazard();
-+			tlb_probe();
-+			tlb_probe_hazard();
-+			idx = read_c0_index();
-+			/* No match or match is on current entry */
-+			if (idx < 0 || idx == entry)
-+				break;
-+			/*
-+			 * If we hit a match, we need to try again with
-+			 * a different ASID.
-+			 */
-+			asid++;
-+		} while (asid < asid_mask);
-+
-+		if (idx >= 0 && idx != entry)
-+			panic("Unable to uniquify TLB entry %d", idx);
-+
-+		write_c0_index(entry);
- 		mtc0_tlbw_hazard();
- 		tlb_write_indexed();
--		tlbw_use_hazard();
-+		entry++;
- 	}
- 
--	sort(tlb_vpns, cnt, sizeof(tlb_vpns[0]), r4k_vpn_cmp, NULL);
--
--	write_c0_pagemask(PM_DEFAULT_MASK);
--	write_c0_entrylo0(0);
--	write_c0_entrylo1(0);
--
--	idx = 0;
--	ent = tlbsize;
--	for (i = start; i < tlbsize; i++)
--		while (1) {
--			unsigned long entryhi, vpn;
--
--			entryhi = UNIQUE_ENTRYHI(ent);
--			vpn = entryhi & vpn_mask & PAGE_MASK;
--
--			if (idx >= cnt || vpn < tlb_vpns[idx]) {
--				write_c0_entryhi(entryhi);
--				write_c0_index(i);
--				mtc0_tlbw_hazard();
--				tlb_write_indexed();
--				ent++;
--				break;
--			} else if (vpn == tlb_vpns[idx]) {
--				ent++;
--			} else {
--				idx++;
--			}
--		}
--
- 	tlbw_use_hazard();
- 	htw_start();
- 	flush_micro_tlb();
-@@ -627,7 +602,6 @@ static void r4k_tlb_configure(void)
- 
- 	/* From this point on the ARC firmware is dead.	 */
- 	r4k_tlb_uniquify();
--	local_flush_tlb_all();
- 
- 	/* Did I tell you that ARC SUCKS?  */
- }