Merge tag 's390-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Vasily Gorbik:

 - Add support for IBM z15 machines.

 - Add SHA3 and CCA AES cipher key support in zcrypt and pkey
   refactoring.

 - Move to arch_stack_walk infrastructure for the stack unwinder.

 - Various kasan fixes and improvements.

 - Various command line parsing fixes.

 - Improve decompressor phase debuggability.

 - Lift no bss usage restriction for the early code.

 - Use refcount_t for reference counters for couple of places in mm
   code.

 - Logging improvements and return code fix in vfio-ccw code.

 - Couple of zpci fixes and minor refactoring.

 - Remove some outdated documentation.

 - Fix secure boot detection.

 - Other various minor code clean ups.

* tag 's390-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
  s390: remove pointless drivers-y in drivers/s390/Makefile
  s390/cpum_sf: Fix line length and format string
  s390/pci: fix MSI message data
  s390: add support for IBM z15 machines
  s390/crypto: Support for SHA3 via CPACF (MSA6)
  s390/startup: add pgm check info printing
  s390/crypto: xts-aes-s390 fix extra run-time crypto self tests finding
  vfio-ccw: fix error return code in vfio_ccw_sch_init()
  s390: vfio-ap: fix warning reset not completed
  s390/base: remove unused s390_base_mcck_handler
  s390/sclp: Fix bit checked for has_sipl
  s390/zcrypt: fix wrong handling of cca cipher keygenflags
  s390/kasan: add kdump support
  s390/setup: avoid using strncmp with hardcoded length
  s390/sclp: avoid using strncmp with hardcoded length
  s390/module: avoid using strncmp with hardcoded length
  s390/pci: avoid using strncmp with hardcoded length
  s390/kaslr: reserve memory for kasan usage
  s390/mem_detect: provide single get_mem_detect_end
  s390/cmma: reuse kstrtobool for option value parsing
  ...

1 files changed, 33 insertions, 8 deletions

diff --git a/arch/s390/boot/kaslr.c b/arch/s390/boot/kaslr.c
index c34a6387ce38..5d12352545c5 100644
--- a/arch/s390/boot/kaslr.c
+++ b/arch/s390/boot/kaslr.c
@@ -3,6 +3,7 @@
  * Copyright IBM Corp. 2019
  */
 #include <asm/mem_detect.h>
+#include <asm/pgtable.h>
 #include <asm/cpacf.h>
 #include <asm/timex.h>
 #include <asm/sclp.h>
@@ -90,8 +91,10 @@ static unsigned long get_random(unsigned long limit)
 
 unsigned long get_random_base(unsigned long safe_addr)
 {
+	unsigned long memory_limit = memory_end_set ? memory_end : 0;
 	unsigned long base, start, end, kernel_size;
 	unsigned long block_sum, offset;
+	unsigned long kasan_needs;
 	int i;
 
 	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && INITRD_START && INITRD_SIZE) {
@@ -100,14 +103,36 @@ unsigned long get_random_base(unsigned long safe_addr)
 	}
 	safe_addr = ALIGN(safe_addr, THREAD_SIZE);
 
+	if ((IS_ENABLED(CONFIG_KASAN))) {
+		/*
+		 * Estimate kasan memory requirements, which it will reserve
+		 * at the very end of available physical memory. To estimate
+		 * that, we take into account that kasan would require
+		 * 1/8 of available physical memory (for shadow memory) +
+		 * creating page tables for the whole memory + shadow memory
+		 * region (1 + 1/8). To keep page tables estimates simple take
+		 * the double of combined ptes size.
+		 */
+		memory_limit = get_mem_detect_end();
+		if (memory_end_set && memory_limit > memory_end)
+			memory_limit = memory_end;
+
+		/* for shadow memory */
+		kasan_needs = memory_limit / 8;
+		/* for paging structures */
+		kasan_needs += (memory_limit + kasan_needs) / PAGE_SIZE /
+			       _PAGE_ENTRIES * _PAGE_TABLE_SIZE * 2;
+		memory_limit -= kasan_needs;
+	}
+
 	kernel_size = vmlinux.image_size + vmlinux.bss_size;
 	block_sum = 0;
 	for_each_mem_detect_block(i, &start, &end) {
-		if (memory_end_set) {
-			if (start >= memory_end)
+		if (memory_limit) {
+			if (start >= memory_limit)
 				break;
-			if (end > memory_end)
-				end = memory_end;
+			if (end > memory_limit)
+				end = memory_limit;
 		}
 		if (end - start < kernel_size)
 			continue;
@@ -125,11 +150,11 @@ unsigned long get_random_base(unsigned long safe_addr)
 		base = safe_addr;
 	block_sum = offset = 0;
 	for_each_mem_detect_block(i, &start, &end) {
-		if (memory_end_set) {
-			if (start >= memory_end)
+		if (memory_limit) {
+			if (start >= memory_limit)
 				break;
-			if (end > memory_end)
-				end = memory_end;
+			if (end > memory_limit)
+				end = memory_limit;
 		}
 		if (end - start < kernel_size)
 			continue;