[GIT PULL] x86 fixes

From: Ingo Molnar
Date: Sat Apr 27 2019 - 10:43:09 EST


Linus,

Please pull the latest x86-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-urgent-for-linus

# HEAD: 0d02113b31b2017dd349ec9df2314e798a90fa6e x86/mm: Fix a crash with kmemleak_scan()

Two fixes:

- Fix an early boot crash in the RSDP parsing code by effectively
turning off the parsing call - we ran out of time but want to fix the
regression. The more involved fix is being worked on.

- Fix a crash that can trigger in the kmemlek code.

Thanks,

Ingo

------------------>
Borislav Petkov (1):
x86/boot: Disable RSDP parsing temporarily

Qian Cai (1):
x86/mm: Fix a crash with kmemleak_scan()


arch/x86/boot/compressed/misc.c | 2 +-
arch/x86/mm/init.c | 6 ++++++
2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/x86/boot/compressed/misc.c b/arch/x86/boot/compressed/misc.c
index c0d6c560df69..5a237e8dbf8d 100644
--- a/arch/x86/boot/compressed/misc.c
+++ b/arch/x86/boot/compressed/misc.c
@@ -352,7 +352,7 @@ asmlinkage __visible void *extract_kernel(void *rmode, memptr heap,
boot_params->hdr.loadflags &= ~KASLR_FLAG;

/* Save RSDP address for later use. */
- boot_params->acpi_rsdp_addr = get_rsdp_addr();
+ /* boot_params->acpi_rsdp_addr = get_rsdp_addr(); */

sanitize_boot_params(boot_params);

diff --git a/arch/x86/mm/init.c b/arch/x86/mm/init.c
index f905a2371080..8dacdb96899e 100644
--- a/arch/x86/mm/init.c
+++ b/arch/x86/mm/init.c
@@ -5,6 +5,7 @@
#include <linux/memblock.h>
#include <linux/swapfile.h>
#include <linux/swapops.h>
+#include <linux/kmemleak.h>

#include <asm/set_memory.h>
#include <asm/e820/api.h>
@@ -766,6 +767,11 @@ void free_init_pages(const char *what, unsigned long begin, unsigned long end)
if (debug_pagealloc_enabled()) {
pr_info("debug: unmapping init [mem %#010lx-%#010lx]\n",
begin, end - 1);
+ /*
+ * Inform kmemleak about the hole in the memory since the
+ * corresponding pages will be unmapped.
+ */
+ kmemleak_free_part((void *)begin, end - begin);
set_memory_np(begin, (end - begin) >> PAGE_SHIFT);
} else {
/*