Linux 6.6.82

Linux 6.6.82

[Greg Kroah-Hartman]

I'm announcing the release of the 6.6.82 kernel.

All i386 users of the 6.6 kernel series must upgrade (as they skipped
the last release.)  All other arches can skip this one as it should not
affect them.

The updated 6.6.y git tree can be found at:
	git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git linux-6.6.y
and can be browsed at the normal kernel.org git web browser:
	https://git.kernel.org/?p=linux/kernel/git/stable/linux-stable.git;a=summary

thanks,

greg k-h

------------

 Makefile                         |    2 
 arch/x86/Kconfig                 |    4 +
 arch/x86/include/asm/microcode.h |    2 
 arch/x86/include/asm/setup.h     |    1 
 arch/x86/kernel/Makefile         |    1 
 arch/x86/kernel/head32.c         |  117 ++++++++++++++++++++++++++++-----------
 6 files changed, 93 insertions(+), 34 deletions(-)

Greg Kroah-Hartman (1):
      Linux 6.6.82

Thomas Gleixner (6):
      x86/boot/32: Disable stackprotector and tracing for mk_early_pgtbl_32()
      x86/boot: Use __pa_nodebug() in mk_early_pgtbl_32()
      x86/boot/32: De-uglify the 2/3 level paging difference in mk_early_pgtbl_32()
      x86/boot/32: Restructure mk_early_pgtbl_32()
      x86/microcode: Provide CONFIG_MICROCODE_INITRD32
      x86/boot/32: Temporarily map initrd for microcode loading

Re: Linux 6.6.82

[Greg Kroah-Hartman]

diff --git a/Makefile b/Makefile
index 892ed237b1e1..bca0f2e14c5c 100644
--- a/Makefile
+++ b/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 VERSION = 6
 PATCHLEVEL = 6
-SUBLEVEL = 81
+SUBLEVEL = 82
 EXTRAVERSION =
 NAME = Pinguïn Aangedreven
 
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 1e666454ebdc..a06fab5016fd 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -1315,6 +1315,10 @@ config MICROCODE
 	depends on CPU_SUP_AMD || CPU_SUP_INTEL
 	select CRYPTO_LIB_SHA256 if CPU_SUP_AMD
 
+config MICROCODE_INITRD32
+	def_bool y
+	depends on MICROCODE && X86_32 && BLK_DEV_INITRD
+
 config MICROCODE_LATE_LOADING
 	bool "Late microcode loading (DANGEROUS)"
 	default n
diff --git a/arch/x86/include/asm/microcode.h b/arch/x86/include/asm/microcode.h
index 1ab475a518e9..0ee6ed0ff2bf 100644
--- a/arch/x86/include/asm/microcode.h
+++ b/arch/x86/include/asm/microcode.h
@@ -23,6 +23,8 @@ static inline void load_ucode_ap(void) { }
 static inline void microcode_bsp_resume(void) { }
 #endif
 
+extern unsigned long initrd_start_early;
+
 #ifdef CONFIG_CPU_SUP_INTEL
 /* Intel specific microcode defines. Public for IFS */
 struct microcode_header_intel {
diff --git a/arch/x86/include/asm/setup.h b/arch/x86/include/asm/setup.h
index f3495623ac99..bf483fcb4e57 100644
--- a/arch/x86/include/asm/setup.h
+++ b/arch/x86/include/asm/setup.h
@@ -126,6 +126,7 @@ void clear_bss(void);
 #ifdef __i386__
 
 asmlinkage void __init __noreturn i386_start_kernel(void);
+void __init mk_early_pgtbl_32(void);
 
 #else
 asmlinkage void __init __noreturn x86_64_start_kernel(char *real_mode);
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 3269a0e23d3a..0000325ab98f 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -16,6 +16,7 @@ CFLAGS_REMOVE_kvmclock.o = -pg
 CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_early_printk.o = -pg
 CFLAGS_REMOVE_head64.o = -pg
+CFLAGS_REMOVE_head32.o = -pg
 CFLAGS_REMOVE_sev.o = -pg
 CFLAGS_REMOVE_rethook.o = -pg
 endif
diff --git a/arch/x86/kernel/head32.c b/arch/x86/kernel/head32.c
index bde27a35bf2e..de001b2146ab 100644
--- a/arch/x86/kernel/head32.c
+++ b/arch/x86/kernel/head32.c
@@ -30,12 +30,32 @@ static void __init i386_default_early_setup(void)
 	x86_init.mpparse.setup_ioapic_ids = setup_ioapic_ids_from_mpc;
 }
 
+#ifdef CONFIG_MICROCODE_INITRD32
+unsigned long __initdata initrd_start_early;
+static pte_t __initdata *initrd_pl2p_start, *initrd_pl2p_end;
+
+static void zap_early_initrd_mapping(void)
+{
+	pte_t *pl2p = initrd_pl2p_start;
+
+	for (; pl2p < initrd_pl2p_end; pl2p++) {
+		*pl2p = (pte_t){ .pte = 0 };
+
+		if (!IS_ENABLED(CONFIG_X86_PAE))
+			*(pl2p + ((PAGE_OFFSET >> PGDIR_SHIFT))) = (pte_t) {.pte = 0};
+	}
+}
+#else
+static inline void zap_early_initrd_mapping(void) { }
+#endif
+
 asmlinkage __visible void __init __noreturn i386_start_kernel(void)
 {
 	/* Make sure IDT is set up before any exception happens */
 	idt_setup_early_handler();
 
 	load_ucode_bsp();
+	zap_early_initrd_mapping();
 
 	cr4_init_shadow();
 
@@ -72,52 +92,83 @@ asmlinkage __visible void __init __noreturn i386_start_kernel(void)
  * to the first kernel PMD. Note the upper half of each PMD or PTE are
  * always zero at this stage.
  */
-void __init mk_early_pgtbl_32(void);
-void __init mk_early_pgtbl_32(void)
-{
-#ifdef __pa
-#undef __pa
-#endif
-#define __pa(x)  ((unsigned long)(x) - PAGE_OFFSET)
-	pte_t pte, *ptep;
-	int i;
-	unsigned long *ptr;
-	/* Enough space to fit pagetables for the low memory linear map */
-	const unsigned long limit = __pa(_end) +
-		(PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT);
 #ifdef CONFIG_X86_PAE
-	pmd_t pl2, *pl2p = (pmd_t *)__pa(initial_pg_pmd);
-#define SET_PL2(pl2, val)    { (pl2).pmd = (val); }
+typedef pmd_t			pl2_t;
+#define pl2_base		initial_pg_pmd
+#define SET_PL2(val)		{ .pmd = (val), }
 #else
-	pgd_t pl2, *pl2p = (pgd_t *)__pa(initial_page_table);
-#define SET_PL2(pl2, val)   { (pl2).pgd = (val); }
+typedef pgd_t			pl2_t;
+#define pl2_base		initial_page_table
+#define SET_PL2(val)		{ .pgd = (val), }
 #endif
 
-	ptep = (pte_t *)__pa(__brk_base);
-	pte.pte = PTE_IDENT_ATTR;
-
+static __init __no_stack_protector pte_t init_map(pte_t pte, pte_t **ptep, pl2_t **pl2p,
+						  const unsigned long limit)
+{
 	while ((pte.pte & PTE_PFN_MASK) < limit) {
+		pl2_t pl2 = SET_PL2((unsigned long)*ptep | PDE_IDENT_ATTR);
+		int i;
+
+		**pl2p = pl2;
+		if (!IS_ENABLED(CONFIG_X86_PAE)) {
+			/* Kernel PDE entry */
+			*(*pl2p + ((PAGE_OFFSET >> PGDIR_SHIFT))) = pl2;
+		}
 
-		SET_PL2(pl2, (unsigned long)ptep | PDE_IDENT_ATTR);
-		*pl2p = pl2;
-#ifndef CONFIG_X86_PAE
-		/* Kernel PDE entry */
-		*(pl2p +  ((PAGE_OFFSET >> PGDIR_SHIFT))) = pl2;
-#endif
 		for (i = 0; i < PTRS_PER_PTE; i++) {
-			*ptep = pte;
+			**ptep = pte;
 			pte.pte += PAGE_SIZE;
-			ptep++;
+			(*ptep)++;
 		}
-
-		pl2p++;
+		(*pl2p)++;
 	}
+	return pte;
+}
+
+void __init __no_stack_protector mk_early_pgtbl_32(void)
+{
+	/* Enough space to fit pagetables for the low memory linear map */
+	unsigned long limit = __pa_nodebug(_end) + (PAGE_TABLE_SIZE(LOWMEM_PAGES) << PAGE_SHIFT);
+	pte_t pte, *ptep = (pte_t *)__pa_nodebug(__brk_base);
+	struct boot_params __maybe_unused *params;
+	pl2_t *pl2p = (pl2_t *)__pa_nodebug(pl2_base);
+	unsigned long *ptr;
+
+	pte.pte = PTE_IDENT_ATTR;
+	pte = init_map(pte, &ptep, &pl2p, limit);
 
-	ptr = (unsigned long *)__pa(&max_pfn_mapped);
+	ptr = (unsigned long *)__pa_nodebug(&max_pfn_mapped);
 	/* Can't use pte_pfn() since it's a call with CONFIG_PARAVIRT */
 	*ptr = (pte.pte & PTE_PFN_MASK) >> PAGE_SHIFT;
 
-	ptr = (unsigned long *)__pa(&_brk_end);
+	ptr = (unsigned long *)__pa_nodebug(&_brk_end);
 	*ptr = (unsigned long)ptep + PAGE_OFFSET;
-}
 
+#ifdef CONFIG_MICROCODE_INITRD32
+	/* Running on a hypervisor? */
+	if (native_cpuid_ecx(1) & BIT(31))
+		return;
+
+	params = (struct boot_params *)__pa_nodebug(&boot_params);
+	if (!params->hdr.ramdisk_size || !params->hdr.ramdisk_image)
+		return;
+
+	/* Save the virtual start address */
+	ptr = (unsigned long *)__pa_nodebug(&initrd_start_early);
+	*ptr = (pte.pte & PTE_PFN_MASK) + PAGE_OFFSET;
+	*ptr += ((unsigned long)params->hdr.ramdisk_image) & ~PAGE_MASK;
+
+	/* Save PLP2 for cleanup */
+	ptr = (unsigned long *)__pa_nodebug(&initrd_pl2p_start);
+	*ptr = (unsigned long)pl2p + PAGE_OFFSET;
+
+	limit = (unsigned long)params->hdr.ramdisk_image;
+	pte.pte = PTE_IDENT_ATTR | PFN_ALIGN(limit);
+	limit = (unsigned long)params->hdr.ramdisk_image + params->hdr.ramdisk_size;
+
+	init_map(pte, &ptep, &pl2p, limit);
+
+	ptr = (unsigned long *)__pa_nodebug(&initrd_pl2p_end);
+	*ptr = (unsigned long)pl2p + PAGE_OFFSET;
+#endif
+}