Updated to 5.12.12

8 files changed, 705 insertions, 5 deletions

diff --git a/0002-x86-setup-Consolidate-early-memory-reservations.patch b/0002-x86-setup-Consolidate-early-memory-reservations.patch
new file mode 100644
index 0000000..8f4fc10
--- /dev/null
+++ b/0002-x86-setup-Consolidate-early-memory-reservations.patch
@@ -0,0 +1,188 @@
+From d95db8299235d164f12f11b0ea8acd60c7e13dcf Mon Sep 17 00:00:00 2001
+From: Mike Rapoport <rppt@linux.ibm.com>
+Date: Tue, 2 Mar 2021 12:04:05 +0200
+Subject: x86/setup: Consolidate early memory reservations
+
+The early reservations of memory areas used by the firmware, bootloader,
+kernel text and data are spread over setup_arch(). Moreover, some of them
+happen *after* memblock allocations, e.g trim_platform_memory_ranges() and
+trim_low_memory_range() are called after reserve_real_mode() that allocates
+memory.
+
+There was no corruption of these memory regions because memblock always
+allocates memory either from the end of memory (in top-down mode) or above
+the kernel image (in bottom-up mode). However, the bottom up mode is going
+to be updated to span the entire memory [1] to avoid limitations caused by
+KASLR.
+
+Consolidate early memory reservations in a dedicated function to improve
+robustness against future changes. Having the early reservations in one
+place also makes it clearer what memory must be reserved before memblock
+allocations are allowed.
+
+Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
+Signed-off-by: Borislav Petkov <bp@suse.de>
+Reviewed-by: Baoquan He <bhe@redhat.com>
+Acked-by: Borislav Petkov <bp@suse.de>
+Acked-by: David Hildenbrand <david@redhat.com>
+Link: [1] https://lore.kernel.org/lkml/20201217201214.3414100-2-guro@fb.com
+Link: https://lkml.kernel.org/r/20210302100406.22059-2-rppt@kernel.org
+---
+ arch/x86/kernel/setup.c | 92 +++++++++++++++++++++++--------------------------
+ 1 file changed, 44 insertions(+), 48 deletions(-)
+
+diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
+index e79f21d13a0d..420d881da2bd 100644
+--- a/arch/x86/kernel/setup.c
++++ b/arch/x86/kernel/setup.c
+@@ -646,18 +646,6 @@ static void __init trim_snb_memory(void)
+ 	}
+ }
+ 
+-/*
+- * Here we put platform-specific memory range workarounds, i.e.
+- * memory known to be corrupt or otherwise in need to be reserved on
+- * specific platforms.
+- *
+- * If this gets used more widely it could use a real dispatch mechanism.
+- */
+-static void __init trim_platform_memory_ranges(void)
+-{
+-	trim_snb_memory();
+-}
+-
+ static void __init trim_bios_range(void)
+ {
+ 	/*
+@@ -730,7 +718,38 @@ static void __init trim_low_memory_range(void)
+ {
+ 	memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
+ }
+-	
++
++static void __init early_reserve_memory(void)
++{
++	/*
++	 * Reserve the memory occupied by the kernel between _text and
++	 * __end_of_kernel_reserve symbols. Any kernel sections after the
++	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
++	 * separate memblock_reserve() or they will be discarded.
++	 */
++	memblock_reserve(__pa_symbol(_text),
++			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
++
++	/*
++	 * Make sure page 0 is always reserved because on systems with
++	 * L1TF its contents can be leaked to user processes.
++	 */
++	memblock_reserve(0, PAGE_SIZE);
++
++	early_reserve_initrd();
++
++	if (efi_enabled(EFI_BOOT))
++		efi_memblock_x86_reserve_range();
++
++	memblock_x86_reserve_range_setup_data();
++
++	reserve_ibft_region();
++	reserve_bios_regions();
++
++	trim_snb_memory();
++	trim_low_memory_range();
++}
++
+ /*
+  * Dump out kernel offset information on panic.
+  */
+@@ -765,29 +784,6 @@ dump_kernel_offset(struct notifier_block *self, unsigned long v, void *p)
+ 
+ void __init setup_arch(char **cmdline_p)
+ {
+-	/*
+-	 * Reserve the memory occupied by the kernel between _text and
+-	 * __end_of_kernel_reserve symbols. Any kernel sections after the
+-	 * __end_of_kernel_reserve symbol must be explicitly reserved with a
+-	 * separate memblock_reserve() or they will be discarded.
+-	 */
+-	memblock_reserve(__pa_symbol(_text),
+-			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
+-
+-	/*
+-	 * Make sure page 0 is always reserved because on systems with
+-	 * L1TF its contents can be leaked to user processes.
+-	 */
+-	memblock_reserve(0, PAGE_SIZE);
+-
+-	early_reserve_initrd();
+-
+-	/*
+-	 * At this point everything still needed from the boot loader
+-	 * or BIOS or kernel text should be early reserved or marked not
+-	 * RAM in e820. All other memory is free game.
+-	 */
+-
+ #ifdef CONFIG_X86_32
+ 	memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
+ 
+@@ -911,8 +907,18 @@ void __init setup_arch(char **cmdline_p)
+ 
+ 	parse_early_param();
+ 
+-	if (efi_enabled(EFI_BOOT))
+-		efi_memblock_x86_reserve_range();
++	/*
++	 * Do some memory reservations *before* memory is added to
++	 * memblock, so memblock allocations won't overwrite it.
++	 * Do it after early param, so we could get (unlikely) panic from
++	 * serial.
++	 *
++	 * After this point everything still needed from the boot loader or
++	 * firmware or kernel text should be early reserved or marked not
++	 * RAM in e820. All other memory is free game.
++	 */
++	early_reserve_memory();
++
+ #ifdef CONFIG_MEMORY_HOTPLUG
+ 	/*
+ 	 * Memory used by the kernel cannot be hot-removed because Linux
+@@ -939,9 +945,6 @@ void __init setup_arch(char **cmdline_p)
+ 
+ 	x86_report_nx();
+ 
+-	/* after early param, so could get panic from serial */
+-	memblock_x86_reserve_range_setup_data();
+-
+ 	if (acpi_mps_check()) {
+ #ifdef CONFIG_X86_LOCAL_APIC
+ 		disable_apic = 1;
+@@ -1033,8 +1036,6 @@ void __init setup_arch(char **cmdline_p)
+ 	 */
+ 	find_smp_config();
+ 
+-	reserve_ibft_region();
+-
+ 	early_alloc_pgt_buf();
+ 
+ 	/*
+@@ -1055,8 +1056,6 @@ void __init setup_arch(char **cmdline_p)
+ 	 */
+ 	sev_setup_arch();
+ 
+-	reserve_bios_regions();
+-
+ 	efi_fake_memmap();
+ 	efi_find_mirror();
+ 	efi_esrt_init();
+@@ -1082,9 +1081,6 @@ void __init setup_arch(char **cmdline_p)
+ 
+ 	reserve_real_mode();
+ 
+-	trim_platform_memory_ranges();
+-	trim_low_memory_range();
+-
+ 	init_mem_mapping();
+ 
+ 	idt_setup_early_pf();
+-- 
+cgit v1.2.3-1-gf6bb5
+
diff --git a/0003-x86-setup-Merge-several-reservations-of-start-of-mem.patch b/0003-x86-setup-Merge-several-reservations-of-start-of-mem.patch
new file mode 100644
index 0000000..13d4141
--- /dev/null
+++ b/0003-x86-setup-Merge-several-reservations-of-start-of-mem.patch
@@ -0,0 +1,67 @@
+From a3a4cc7df405aeff7d70a11ee4e90965809ed09e Mon Sep 17 00:00:00 2001
+From: Mike Rapoport <rppt@linux.ibm.com>
+Date: Tue, 2 Mar 2021 12:04:06 +0200
+Subject: x86/setup: Merge several reservations of start of memory
+
+Currently, the first several pages are reserved both to avoid leaking
+their contents on systems with L1TF and to avoid corrupting BIOS memory.
+
+Merge the two memory reservations.
+
+Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
+Signed-off-by: Borislav Petkov <bp@suse.de>
+Reviewed-by: David Hildenbrand <david@redhat.com>
+Acked-by: Borislav Petkov <bp@suse.de>
+Link: https://lkml.kernel.org/r/20210302100406.22059-3-rppt@kernel.org
+---
+ arch/x86/kernel/setup.c | 19 ++++++++++---------
+ 1 file changed, 10 insertions(+), 9 deletions(-)
+
+diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
+index 420d881da2bd..282d572e49af 100644
+--- a/arch/x86/kernel/setup.c
++++ b/arch/x86/kernel/setup.c
+@@ -714,11 +714,6 @@ static int __init parse_reservelow(char *p)
+ 
+ early_param("reservelow", parse_reservelow);
+ 
+-static void __init trim_low_memory_range(void)
+-{
+-	memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
+-}
+-
+ static void __init early_reserve_memory(void)
+ {
+ 	/*
+@@ -731,10 +726,17 @@ static void __init early_reserve_memory(void)
+ 			 (unsigned long)__end_of_kernel_reserve - (unsigned long)_text);
+ 
+ 	/*
+-	 * Make sure page 0 is always reserved because on systems with
+-	 * L1TF its contents can be leaked to user processes.
++	 * The first 4Kb of memory is a BIOS owned area, but generally it is
++	 * not listed as such in the E820 table.
++	 *
++	 * Reserve the first memory page and typically some additional
++	 * memory (64KiB by default) since some BIOSes are known to corrupt
++	 * low memory. See the Kconfig help text for X86_RESERVE_LOW.
++	 *
++	 * In addition, make sure page 0 is always reserved because on
++	 * systems with L1TF its contents can be leaked to user processes.
+ 	 */
+-	memblock_reserve(0, PAGE_SIZE);
++	memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
+ 
+ 	early_reserve_initrd();
+ 
+@@ -747,7 +749,6 @@ static void __init early_reserve_memory(void)
+ 	reserve_bios_regions();
+ 
+ 	trim_snb_memory();
+-	trim_low_memory_range();
+ }
+ 
+ /*
+-- 
+cgit v1.2.3-1-gf6bb5
+
diff --git a/0004-x86-setup-Move-trim_snb_memory-later-in-setup_arch-t.patch b/0004-x86-setup-Move-trim_snb_memory-later-in-setup_arch-t.patch
new file mode 100644
index 0000000..fd004ef
--- /dev/null
+++ b/0004-x86-setup-Move-trim_snb_memory-later-in-setup_arch-t.patch
@@ -0,0 +1,87 @@
+From 0ad14408305e590f26efe4437f925b40d283e67d Mon Sep 17 00:00:00 2001
+From: Mike Rapoport <rppt@linux.ibm.com>
+Date: Tue, 13 Apr 2021 21:08:39 +0300
+Subject: x86/setup: Move trim_snb_memory() later in setup_arch() to fix boot
+ hangs
+
+Commit
+
+  a799c2bd29d1 ("x86/setup: Consolidate early memory reservations")
+
+moved reservation of the memory inaccessible by Sandy Bride integrated
+graphics very early, and, as a result, on systems with such devices
+the first 1M was reserved by trim_snb_memory() which prevented the
+allocation of the real mode trampoline and made the boot hang very
+early.
+
+Since the purpose of trim_snb_memory() is to prevent problematic pages
+ever reaching the graphics device, it is safe to reserve these pages
+after memblock allocations are possible.
+
+Move trim_snb_memory() later in boot so that it will be called after
+reserve_real_mode() and make comments describing trim_snb_memory()
+operation more elaborate.
+
+ [ bp: Massage a bit. ]
+
+Fixes: a799c2bd29d1 ("x86/setup: Consolidate early memory reservations")
+Reported-by: Randy Dunlap <rdunlap@infradead.org>
+Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
+Signed-off-by: Borislav Petkov <bp@suse.de>
+Tested-by: Randy Dunlap <rdunlap@infradead.org>
+Tested-by: Hugh Dickins <hughd@google.com>
+Link: https://lkml.kernel.org/r/f67d3e03-af90-f790-baf4-8d412fe055af@infradead.org
+---
+ arch/x86/kernel/setup.c | 20 +++++++++++++++-----
+ 1 file changed, 15 insertions(+), 5 deletions(-)
+
+diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
+index 282d572e49af..7d466f51be1f 100644
+--- a/arch/x86/kernel/setup.c
++++ b/arch/x86/kernel/setup.c
+@@ -634,11 +634,16 @@ static void __init trim_snb_memory(void)
+ 	printk(KERN_DEBUG "reserving inaccessible SNB gfx pages\n");
+ 
+ 	/*
+-	 * Reserve all memory below the 1 MB mark that has not
+-	 * already been reserved.
++	 * SandyBridge integrated graphics devices have a bug that prevents
++	 * them from accessing certain memory ranges, namely anything below
++	 * 1M and in the pages listed in bad_pages[] above.
++	 *
++	 * To avoid these pages being ever accessed by SNB gfx devices
++	 * reserve all memory below the 1 MB mark and bad_pages that have
++	 * not already been reserved at boot time.
+ 	 */
+ 	memblock_reserve(0, 1<<20);
+-	
++
+ 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
+ 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
+ 			printk(KERN_WARNING "failed to reserve 0x%08lx\n",
+@@ -747,8 +752,6 @@ static void __init early_reserve_memory(void)
+ 
+ 	reserve_ibft_region();
+ 	reserve_bios_regions();
+-
+-	trim_snb_memory();
+ }
+ 
+ /*
+@@ -1082,6 +1085,13 @@ void __init setup_arch(char **cmdline_p)
+ 
+ 	reserve_real_mode();
+ 
++	/*
++	 * Reserving memory causing GPU hangs on Sandy Bridge integrated
++	 * graphics devices should be done after we allocated memory under
++	 * 1M for the real mode trampoline.
++	 */
++	trim_snb_memory();
++
+ 	init_mem_mapping();
+ 
+ 	idt_setup_early_pf();
+-- 
+cgit v1.2.3-1-gf6bb5
+
diff --git a/0005-x86-setup-always-reserve-the-first-1M-of-RAM.patch b/0005-x86-setup-always-reserve-the-first-1M-of-RAM.patch
new file mode 100644
index 0000000..6f21224
--- /dev/null
+++ b/0005-x86-setup-always-reserve-the-first-1M-of-RAM.patch
@@ -0,0 +1,170 @@
+From d95f872247541176d4edf5664198ed9edb12f134 Mon Sep 17 00:00:00 2001
+From: Mike Rapoport <rppt@linux.ibm.com>
+Date: Tue, 1 Jun 2021 10:53:52 +0300
+Subject: x86/setup: always reserve the first 1M of RAM
+
+There are BIOSes that are known to corrupt the memory under 1M, or more
+precisely under 640K because the memory above 640K is anyway reserved for
+the EGA/VGA frame buffer and BIOS.
+
+To prevent usage of the memory that will be potentially clobbered by the
+kernel, the beginning of the memory is always reserved. The exact size of
+the reserved area is determined by CONFIG_X86_RESERVE_LOW build time and
+reservelow command line option. The reserved range may be from 4K to 640K
+with the default of 64K. There are also configurations that reserve the
+entire 1M range, like machines with SandyBridge graphic devices or systems
+that enable crash kernel.
+
+In addition to the potentially clobbered memory, EBDA of unknown size may
+be as low as 128K and the memory above that EBDA start is also reserved
+early.
+
+It would have been possible to reserve the entire range under 1M unless for
+the real mode trampoline that must reside in that area.
+
+To accommodate placement of the real mode trampoline and keep the memory
+safe from being clobbered by BIOS reserve the first 64K of RAM before
+memory allocations are possible and then, after the real mode trampoline is
+allocated, reserve the entire range from 0 to 1M.
+
+Update trim_snb_memory() and reserve_real_mode() to avoid redundant
+reservations of the same memory range.
+
+Also make sure the memory under 1M is not getting freed by
+efi_free_boot_services().
+
+Fixes: a799c2bd29d1 ("x86/setup: Consolidate early memory reservations")
+Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
+---
+ arch/x86/kernel/setup.c        | 35 +++++++++++++++++++++--------------
+ arch/x86/platform/efi/quirks.c | 12 ++++++++++++
+ arch/x86/realmode/init.c       | 14 ++++++++------
+ 3 files changed, 41 insertions(+), 20 deletions(-)
+
+diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
+index 7d466f51be1f..d7cfb927864f 100644
+--- a/arch/x86/kernel/setup.c
++++ b/arch/x86/kernel/setup.c
+@@ -638,11 +638,11 @@ static void __init trim_snb_memory(void)
+ 	 * them from accessing certain memory ranges, namely anything below
+ 	 * 1M and in the pages listed in bad_pages[] above.
+ 	 *
+-	 * To avoid these pages being ever accessed by SNB gfx devices
+-	 * reserve all memory below the 1 MB mark and bad_pages that have
+-	 * not already been reserved at boot time.
++	 * To avoid these pages being ever accessed by SNB gfx devices reserve
++	 * bad_pages that have not already been reserved at boot time.
++	 * All memory below the 1 MB mark is anyway reserved later during
++	 * setup_arch(), so there is no need to reserve it here.
+ 	 */
+-	memblock_reserve(0, 1<<20);
+ 
+ 	for (i = 0; i < ARRAY_SIZE(bad_pages); i++) {
+ 		if (memblock_reserve(bad_pages[i], PAGE_SIZE))
+@@ -734,14 +734,14 @@ static void __init early_reserve_memory(void)
+ 	 * The first 4Kb of memory is a BIOS owned area, but generally it is
+ 	 * not listed as such in the E820 table.
+ 	 *
+-	 * Reserve the first memory page and typically some additional
+-	 * memory (64KiB by default) since some BIOSes are known to corrupt
+-	 * low memory. See the Kconfig help text for X86_RESERVE_LOW.
++	 * Reserve the first 64K of memory since some BIOSes are known to
++	 * corrupt low memory. After the real mode trampoline is allocated the
++	 * rest of the memory below 640k is reserved.
+ 	 *
+ 	 * In addition, make sure page 0 is always reserved because on
+ 	 * systems with L1TF its contents can be leaked to user processes.
+ 	 */
+-	memblock_reserve(0, ALIGN(reserve_low, PAGE_SIZE));
++	memblock_reserve(0, SZ_64K);
+ 
+ 	early_reserve_initrd();
+ 
+@@ -752,6 +752,7 @@ static void __init early_reserve_memory(void)
+ 
+ 	reserve_ibft_region();
+ 	reserve_bios_regions();
++	trim_snb_memory();
+ }
+ 
+ /*
+@@ -1083,14 +1084,20 @@ void __init setup_arch(char **cmdline_p)
+ 			(max_pfn_mapped<<PAGE_SHIFT) - 1);
+ #endif
+ 
+-	reserve_real_mode();
+-
+ 	/*
+-	 * Reserving memory causing GPU hangs on Sandy Bridge integrated
+-	 * graphics devices should be done after we allocated memory under
+-	 * 1M for the real mode trampoline.
++	 * Find free memory for the real mode trampoline and place it
++	 * there.
++	 * If there is not enough free memory under 1M, on EFI-enabled
++	 * systems there will be additional attempt to reclaim the memory
++	 * for the real mode trampoline at efi_free_boot_services().
++	 *
++	 * Unconditionally reserve the entire first 1M of RAM because
++	 * BIOSes are know to corrupt low memory and several
++	 * hundred kilobytes are not worth complex detection what memory gets
++	 * clobbered. Moreover, on machines with SandyBridge graphics or in
++	 * setups that use crashkernel the entire 1M is anyway reserved.
+ 	 */
+-	trim_snb_memory();
++	reserve_real_mode();
+ 
+ 	init_mem_mapping();
+ 
+diff --git a/arch/x86/platform/efi/quirks.c b/arch/x86/platform/efi/quirks.c
+index 67d93a243c35..27561b56a821 100644
+--- a/arch/x86/platform/efi/quirks.c
++++ b/arch/x86/platform/efi/quirks.c
+@@ -450,6 +450,18 @@ void __init efi_free_boot_services(void)
+ 			size -= rm_size;
+ 		}
+ 
++		/*
++		 * Don't free memory under 1M for two reasons:
++		 * - BIOS might clobber it
++		 * - Crash kernel needs it to be reserved
++		 */
++		if (start + size < SZ_1M)
++			continue;
++		if (start < SZ_1M) {
++			size -= (SZ_1M - start);
++			start = SZ_1M;
++		}
++
+ 		memblock_free_late(start, size);
+ 	}
+ 
+diff --git a/arch/x86/realmode/init.c b/arch/x86/realmode/init.c
+index 22fda7d99159..ea42630d4e2e 100644
+--- a/arch/x86/realmode/init.c
++++ b/arch/x86/realmode/init.c
+@@ -29,14 +29,16 @@ void __init reserve_real_mode(void)
+ 
+ 	/* Has to be under 1M so we can execute real-mode AP code. */
+ 	mem = memblock_find_in_range(0, 1<<20, size, PAGE_SIZE);
+-	if (!mem) {
++	if (!mem)
+ 		pr_info("No sub-1M memory is available for the trampoline\n");
+-		return;
+-	}
++	else
++		set_real_mode_mem(mem);
+ 
+-	memblock_reserve(mem, size);
+-	set_real_mode_mem(mem);
+-	crash_reserve_low_1M();
++	/*
++	 * Unconditionally reserve the entire fisrt 1M, see comment in
++	 * setup_arch()
++	 */
++	memblock_reserve(0, SZ_1M);
+ }
+ 
+ static void sme_sev_setup_real_mode(struct trampoline_header *th)
+-- 
+cgit v1.2.3-1-gf6bb5
+
diff --git a/0006-x86-setup-remove-CONFIG_X86_RESERVE_LOW-and-reservel.patch b/0006-x86-setup-remove-CONFIG_X86_RESERVE_LOW-and-reservel.patch
new file mode 100644
index 0000000..6da7e39
--- /dev/null
+++ b/0006-x86-setup-remove-CONFIG_X86_RESERVE_LOW-and-reservel.patch
@@ -0,0 +1,113 @@
+From f42fcdafbd9c6232c086bd717fa29f1664ccaadb Mon Sep 17 00:00:00 2001
+From: Mike Rapoport <rppt@linux.ibm.com>
+Date: Tue, 1 Jun 2021 10:53:53 +0300
+Subject: x86/setup: remove CONFIG_X86_RESERVE_LOW and reservelow options
+
+The CONFIG_X86_RESERVE_LOW build time and reservelow command line option
+allowed to control the amount of memory under 1M that would be reserved at
+boot to avoid using memory that can be potentially clobbered by BIOS.
+
+Since the entire range under 1M is always reserved there is no need for
+these options and they can be removed.
+
+Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
+---
+ Documentation/admin-guide/kernel-parameters.txt |  5 -----
+ arch/x86/Kconfig                                | 29 -------------------------
+ arch/x86/kernel/setup.c                         | 24 --------------------
+ 3 files changed, 58 deletions(-)
+
+diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
+index 835f810f2f26..479cc44cc4e2 100644
+--- a/Documentation/admin-guide/kernel-parameters.txt
++++ b/Documentation/admin-guide/kernel-parameters.txt
+@@ -4623,11 +4623,6 @@
+ 			Reserves a hole at the top of the kernel virtual
+ 			address space.
+ 
+-	reservelow=	[X86]
+-			Format: nn[K]
+-			Set the amount of memory to reserve for BIOS at
+-			the bottom of the address space.
+-
+ 	reset_devices	[KNL] Force drivers to reset the underlying device
+ 			during initialization.
+ 
+diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
+index 861b1b794697..fc91be3b1bd1 100644
+--- a/arch/x86/Kconfig
++++ b/arch/x86/Kconfig
+@@ -1688,35 +1688,6 @@ config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
+ 	  Set whether the default state of memory_corruption_check is
+ 	  on or off.
+ 
+-config X86_RESERVE_LOW
+-	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
+-	default 64
+-	range 4 640
+-	help
+-	  Specify the amount of low memory to reserve for the BIOS.
+-
+-	  The first page contains BIOS data structures that the kernel
+-	  must not use, so that page must always be reserved.
+-
+-	  By default we reserve the first 64K of physical RAM, as a
+-	  number of BIOSes are known to corrupt that memory range
+-	  during events such as suspend/resume or monitor cable
+-	  insertion, so it must not be used by the kernel.
+-
+-	  You can set this to 4 if you are absolutely sure that you
+-	  trust the BIOS to get all its memory reservations and usages
+-	  right.  If you know your BIOS have problems beyond the
+-	  default 64K area, you can set this to 640 to avoid using the
+-	  entire low memory range.
+-
+-	  If you have doubts about the BIOS (e.g. suspend/resume does
+-	  not work or there's kernel crashes after certain hardware
+-	  hotplug events) then you might want to enable
+-	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
+-	  typical corruption patterns.
+-
+-	  Leave this to the default value of 64 if you are unsure.
+-
+ config MATH_EMULATION
+ 	bool
+ 	depends on MODIFY_LDT_SYSCALL
+diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
+index d7cfb927864f..fbda4bbf75c1 100644
+--- a/arch/x86/kernel/setup.c
++++ b/arch/x86/kernel/setup.c
+@@ -695,30 +695,6 @@ static void __init e820_add_kernel_range(void)
+ 	e820__range_add(start, size, E820_TYPE_RAM);
+ }
+ 
+-static unsigned reserve_low = CONFIG_X86_RESERVE_LOW << 10;
+-
+-static int __init parse_reservelow(char *p)
+-{
+-	unsigned long long size;
+-
+-	if (!p)
+-		return -EINVAL;
+-
+-	size = memparse(p, &p);
+-
+-	if (size < 4096)
+-		size = 4096;
+-
+-	if (size > 640*1024)
+-		size = 640*1024;
+-
+-	reserve_low = size;
+-
+-	return 0;
+-}
+-
+-early_param("reservelow", parse_reservelow);
+-
+ static void __init early_reserve_memory(void)
+ {
+ 	/*
+-- 
+cgit v1.2.3-1-gf6bb5
+
diff --git a/0007-x86-crash-remove-crash_reserve_low_1M.patch b/0007-x86-crash-remove-crash_reserve_low_1M.patch
new file mode 100644
index 0000000..92dbb94
--- /dev/null
+++ b/0007-x86-crash-remove-crash_reserve_low_1M.patch
@@ -0,0 +1,58 @@
+From 74d8a788eff7fd6cfed8aa5901a6abf3d6b5be7f Mon Sep 17 00:00:00 2001
+From: Mike Rapoport <rppt@linux.ibm.com>
+Date: Tue, 1 Jun 2021 10:53:54 +0300
+Subject: x86/crash: remove crash_reserve_low_1M()
+
+The entire memory range under 1M is unconditionally reserved at
+setup_arch(), so there is no need for crash_reserve_low_1M() anymore.
+
+Remove this function.
+
+Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
+---
+ arch/x86/include/asm/crash.h |  6 ------
+ arch/x86/kernel/crash.c      | 13 -------------
+ 2 files changed, 19 deletions(-)
+
+diff --git a/arch/x86/include/asm/crash.h b/arch/x86/include/asm/crash.h
+index f58de66091e5..8b6bd63530dc 100644
+--- a/arch/x86/include/asm/crash.h
++++ b/arch/x86/include/asm/crash.h
+@@ -9,10 +9,4 @@ int crash_setup_memmap_entries(struct kimage *image,
+ 		struct boot_params *params);
+ void crash_smp_send_stop(void);
+ 
+-#ifdef CONFIG_KEXEC_CORE
+-void __init crash_reserve_low_1M(void);
+-#else
+-static inline void __init crash_reserve_low_1M(void) { }
+-#endif
+-
+ #endif /* _ASM_X86_CRASH_H */
+diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c
+index b1deacbeb266..e0b8d9662da5 100644
+--- a/arch/x86/kernel/crash.c
++++ b/arch/x86/kernel/crash.c
+@@ -70,19 +70,6 @@ static inline void cpu_crash_vmclear_loaded_vmcss(void)
+ 	rcu_read_unlock();
+ }
+ 
+-/*
+- * When the crashkernel option is specified, only use the low
+- * 1M for the real mode trampoline.
+- */
+-void __init crash_reserve_low_1M(void)
+-{
+-	if (cmdline_find_option(boot_command_line, "crashkernel", NULL, 0) < 0)
+-		return;
+-
+-	memblock_reserve(0, 1<<20);
+-	pr_info("Reserving the low 1M of memory for crashkernel\n");
+-}
+-
+ #if defined(CONFIG_SMP) && defined(CONFIG_X86_LOCAL_APIC)
+ 
+ static void kdump_nmi_callback(int cpu, struct pt_regs *regs)
+-- 
+cgit v1.2.3-1-gf6bb5
+
diff --git a/PKGBUILD b/PKGBUILD
index 0cb3420..3cdcab4 100644
--- a/PKGBUILD
+++ b/PKGBUILD
@@ -23,7 +23,7 @@ _custom=1
 pkgbase=linux-ck
 _supver=5
 _majver=12
-_minver=10
+_minver=12
 _gccpatchver='20210610'
 _gccpatchger='10'
 _gccpatchker='5.8'
@@ -51,6 +51,12 @@ source=(
   config         # the main kernel config file
   linux-ck-patch-${_supver}.${_majver}-${_ckpatchversion}.xz::http://ck.kolivas.org/patches/${_supver}.0/${_supver}.${_majver}/${_supver}.${_majver}-${_ckpatchversion}/patch-${_supver}.${_majver}-${_ckpatchversion}.xz
   ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
+  0002-x86-setup-Consolidate-early-memory-reservations.patch
+  0003-x86-setup-Merge-several-reservations-of-start-of-mem.patch
+  0004-x86-setup-Move-trim_snb_memory-later-in-setup_arch-t.patch
+  0005-x86-setup-always-reserve-the-first-1M-of-RAM.patch
+  0006-x86-setup-remove-CONFIG_X86_RESERVE_LOW-and-reservel.patch
+  0007-x86-crash-remove-crash_reserve_low_1M.patch
   kernel_compiler_patch-${_gccpatchver}.tar.gz::https://github.com/graysky2/kernel_compiler_patch/archive/${_gccpatchver}.tar.gz
   ath9k-regdom-hack.patch
   raid6-default-algo.patch
@@ -60,11 +66,17 @@ validpgpkeys=(
   '647F28654894E3BD457199BE38DBBDC86092693E'  # Greg Kroah-Hartman
 )
 # https://www.kernel.org/pub/linux/kernel/v5.x/sha256sums.asc
-b2sums=('b40ef5a11ca435299899e8131fa72af147455cd8ebee4c0e187572b1f628e66d2b6fbb318308bc911a598d8303d1ab3622d52966deaa5c48d59dcd65f4f58687'
+b2sums=('f9aef3da2f65916cc30da9a066217d3379036e6a32a732224da7fee86c80810315484f48132b50b8cf8eb5e0b055ad1b7bbe63dadd0eb54b0b0626bc57c20963'
         'SKIP'
-        'a40ce1491df4f8fdc7c1ed9bd3937b9b350c34f0c4704150368026f26a5a73c8ec9ddcf7b0070243596278e7262958e0f9f2ab080ca7a3e243a07bf9664e94a4'
+        '11dad93c6b159798eeef9d343fdb046b0b4b1ae93f339be38e0bc8707000ac7935f2c1594307d0845e28016cb5bab0366cadfd69fb81efc06055e39b6835c4a9'
         'c9f729ba1efe6f04e7b2c57d3999bc9675b577596dccb2f227e5b6e444285e1fdd270bf67c0fcf9f5808a4c3a4b1c7a5c13a76f754ad9b9447243ccbaf2ce6a3'
         '2f9195675270d79d735a3aaec25887c2f80b76eae98be8fcc5fd59ab71d925c5ee20ec5e2a015deb68b61bc2cc7f56f546a22cb96ee038e2e24c2c9dd5c3f79f'
+        '3a1a77419b060c8da3cd1357f4d62675f61f271a328ac3c8e7d2d202b430e4aed8183431e23d159e01c0b35a10ffb0da8fedebe5e446d276614bb447e84caf15'
+        '018651b7c5ba0010b134d032995ac6c2ed2b0262394a2d4811d6c0350c4cdf04aaeea0126dd5a79f79859988c320c0f22164a3f58e7f0a9e54981215f147b33a'
+        'b6ea62d9bbbc9852bc6869bdaada00077d77a9120e5884c3386a73ddd56a2d2443c666fba1febcf2f810b148d32a21b55f8701f5813da9374a958d9de4d6df31'
+        '1f352876f4f6eddd9ec8991c3fea3c21f568f2818a7d0633893b64ca1d7cdb56644adf7fef2bbc6176e29920c2860a3c49c1e390905cbe4d2b2be4dda9c4693f'
+        '18d680cc1cb4980822754ca7f679035fa06e9077c35ac2b41acd953ca48cdc3f96224336624033ae9a1adcd886773ca8fa06c2e083cc65885da4bb7c755bd950'
+        '067a8587ff19b2fd29b24f3603348d71999a19e0551bc65f54521991cfcd4121bdd707b14438858639f4533e50323e0b0960f12e9980a1b086508c29a6a5fc2d'
         '30d1df754608bb423cbc99c2097ad521baa091b9a3b39df4bd5c2d50c57eec54d8fa0e4a4a04b847c3d1b87ba682cadc8db45fabeefdc9ad7caaf8e77b96e41a'
         'b6ef77035611139fa9a6d5b8d30570e2781bb4da483bb569884b0bd0129b62e0b82a5a6776fefe43fee801c70d39de1ea4d4c177f7cedd5ac135e3c64f7b895a'
         'fde132f3705d908e6f2147c78a2193289916d72304ca5efa2229d79fc3e57a857314ce94e71425caef2f7f7b6cf87f05ef86335dc8bd4be78e7035afe608005a')
@@ -86,6 +98,12 @@ prepare() {
   # Hotfixes
   echo "Applying hotfixes"
   patch -p1 -i ../ZEN-Add-sysctl-and-CONFIG-to-disallow-unprivileged-C.patch
+  patch -p1 -i ../0002-x86-setup-Consolidate-early-memory-reservations.patch
+  patch -p1 -i ../0003-x86-setup-Merge-several-reservations-of-start-of-mem.patch
+  patch -p1 -i ../0004-x86-setup-Move-trim_snb_memory-later-in-setup_arch-t.patch
+  patch -p1 -i ../0005-x86-setup-always-reserve-the-first-1M-of-RAM.patch
+  patch -p1 -i ../0006-x86-setup-remove-CONFIG_X86_RESERVE_LOW-and-reservel.patch
+  patch -p1 -i ../0007-x86-crash-remove-crash_reserve_low_1M.patch
 
 
   # ck patch
diff --git a/config b/config
index 1d983b4..cd40df1 100644
--- a/config
+++ b/config
@@ -1,6 +1,6 @@
 #
 # Automatically generated file; DO NOT EDIT.
-# Linux/x86 5.12.7 Kernel Configuration
+# Linux/x86 5.12.12 Kernel Configuration
 #
 CONFIG_CC_VERSION_TEXT="gcc (GCC) 11.1.0"
 CONFIG_CC_IS_GCC=y
@@ -480,7 +480,6 @@ CONFIG_X86_PMEM_LEGACY_DEVICE=y
 CONFIG_X86_PMEM_LEGACY=m
 CONFIG_X86_CHECK_BIOS_CORRUPTION=y
 CONFIG_X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK=y
-CONFIG_X86_RESERVE_LOW=64
 CONFIG_MTRR=y
 CONFIG_MTRR_SANITIZER=y
 CONFIG_MTRR_SANITIZER_ENABLE_DEFAULT=1