[GIT PULL] s390 updates for 6.2-rc4

From: Heiko Carstens
Date: Thu Jan 12 2023 - 13:21:33 EST

Hello Linus,

please pull s390 updates for 6.2-rc4.

Thanks,
Heiko

The following changes since commit 88603b6dc419445847923fcb7fe5080067a30f98:

Linux 6.2-rc2 (2023-01-01 13:53:16 -0800)

are available in the Git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git tags/s390-6.2-2

for you to fetch changes up to 1ecf7bd9c267ab85aff3c4a17fe56bc9754a13be:

s390: update defconfigs (2023-01-11 21:26:40 +0100)

----------------------------------------------------------------
s390 updates for 6.2-rc4

- Add various missing READ_ONCE() to cmpxchg() loops prevent the compiler
from potentially generating incorrect code. This includes a rather large
change to the s390 specific hardware sampling code and its current use of
cmpxchg_double().
Do the fix now to get it out of the way of Peter Zijlstra's cmpxchg128()
work, and have something that can be backported. The added new code
includes a private 128 bit cmpxchg variant which will be removed again
after Peter's rework is available. Also note that this 128 bit cmpxchg
variant is used to implement 128 bit READ_ONCE(), while strictly speaking
it wouldn't be necessary, and _READ_ONCE() should also be sufficient;
even though it isn't obvious for all converted locations that this is the
case. Therefore use this implementation for for the sake of clarity and
consistency for now.

- Fix ipl report address handling to avoid kdump failures/hangs.

- Fix misuse of #(el)if in kernel decompressor.

- Define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36, caused
by the recently changed discard behaviour.

- Make sure _edata and _end symbols are always page aligned.

- The current header guard DEBUG_H in one of the s390 specific header files
is too generic and conflicts with the ath9k wireless driver. Add an
_ASM_S390_ prefix to the guard to make it unique.

- Update defconfigs.

----------------------------------------------------------------
Alexander Egorenkov (1):
s390/kexec: fix ipl report address for kdump

Alexander Gordeev (1):
s390: expicitly align _edata and _end symbols on page boundary

Heiko Carstens (4):
s390/cpum_sf: add READ_ONCE() semantics to compare and swap loops
s390/percpu: add READ_ONCE() to arch_this_cpu_to_op_simple()
KVM: s390: interrupt: use READ_ONCE() before cmpxchg()
s390: update defconfigs

Masahiro Yamada (2):
s390: define RUNTIME_DISCARD_EXIT to fix link error with GNU ld < 2.36
s390: fix -Wundef warning for CONFIG_KERNEL_ZSTD

Niklas Schnelle (1):
s390/debug: add _ASM_S390_ prefix to header guard

arch/s390/boot/decompressor.c | 4 +-
arch/s390/configs/debug_defconfig | 7 ++-
arch/s390/configs/defconfig | 6 +-
arch/s390/configs/zfcpdump_defconfig | 2 +-
arch/s390/include/asm/cpu_mf.h | 31 +++++------
arch/s390/include/asm/debug.h | 6 +-
arch/s390/include/asm/percpu.h | 2 +-
arch/s390/kernel/machine_kexec_file.c | 5 +-
arch/s390/kernel/perf_cpum_sf.c | 101 +++++++++++++++++++++-------------
arch/s390/kernel/vmlinux.lds.S | 4 ++
arch/s390/kvm/interrupt.c | 12 ++--
11 files changed, 107 insertions(+), 73 deletions(-)

diff --git a/arch/s390/boot/decompressor.c b/arch/s390/boot/decompressor.c
index e27c2140d620..8dcd7af2911a 100644
--- a/arch/s390/boot/decompressor.c
+++ b/arch/s390/boot/decompressor.c
@@ -23,9 +23,9 @@
#define memmove memmove
#define memzero(s, n) memset((s), 0, (n))

-#ifdef CONFIG_KERNEL_BZIP2
+#if defined(CONFIG_KERNEL_BZIP2)
#define BOOT_HEAP_SIZE 0x400000
-#elif CONFIG_KERNEL_ZSTD
+#elif defined(CONFIG_KERNEL_ZSTD)
#define BOOT_HEAP_SIZE 0x30000
#else
#define BOOT_HEAP_SIZE 0x10000
diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index a7b4e1d82758..74b35ec2ad28 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -190,7 +190,6 @@ CONFIG_NFT_CT=m
CONFIG_NFT_LOG=m
CONFIG_NFT_LIMIT=m
CONFIG_NFT_NAT=m
-CONFIG_NFT_OBJREF=m
CONFIG_NFT_REJECT=m
CONFIG_NFT_COMPAT=m
CONFIG_NFT_HASH=m
@@ -569,6 +568,7 @@ CONFIG_INPUT_EVDEV=y
# CONFIG_INPUT_MOUSE is not set
# CONFIG_SERIO is not set
CONFIG_LEGACY_PTY_COUNT=0
+# CONFIG_LEGACY_TIOCSTI is not set
CONFIG_VIRTIO_CONSOLE=m
CONFIG_HW_RANDOM_VIRTIO=m
CONFIG_HANGCHECK_TIMER=m
@@ -660,6 +660,7 @@ CONFIG_CONFIGFS_FS=m
CONFIG_ECRYPT_FS=m
CONFIG_CRAMFS=m
CONFIG_SQUASHFS=m
+CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT=y
CONFIG_SQUASHFS_XATTR=y
CONFIG_SQUASHFS_LZ4=y
CONFIG_SQUASHFS_LZO=y
@@ -705,6 +706,7 @@ CONFIG_SECURITY_LOCKDOWN_LSM_EARLY=y
CONFIG_SECURITY_LANDLOCK=y
CONFIG_INTEGRITY_SIGNATURE=y
CONFIG_INTEGRITY_ASYMMETRIC_KEYS=y
+CONFIG_INTEGRITY_PLATFORM_KEYRING=y
CONFIG_IMA=y
CONFIG_IMA_DEFAULT_HASH_SHA256=y
CONFIG_IMA_WRITE_POLICY=y
@@ -781,6 +783,7 @@ CONFIG_ZCRYPT=m
CONFIG_PKEY=m
CONFIG_CRYPTO_PAES_S390=m
CONFIG_CRYPTO_DEV_VIRTIO=m
+CONFIG_SYSTEM_BLACKLIST_KEYRING=y
CONFIG_CORDIC=m
CONFIG_CRYPTO_LIB_CURVE25519=m
CONFIG_CRYPTO_LIB_CHACHA20POLY1305=m
@@ -848,7 +851,6 @@ CONFIG_PREEMPT_TRACER=y
CONFIG_SCHED_TRACER=y
CONFIG_FTRACE_SYSCALLS=y
CONFIG_BLK_DEV_IO_TRACE=y
-CONFIG_BPF_KPROBE_OVERRIDE=y
CONFIG_HIST_TRIGGERS=y
CONFIG_FTRACE_STARTUP_TEST=y
# CONFIG_EVENT_TRACE_STARTUP_TEST is not set
@@ -870,7 +872,6 @@ CONFIG_FAIL_MAKE_REQUEST=y
CONFIG_FAIL_IO_TIMEOUT=y
CONFIG_FAIL_FUTEX=y
CONFIG_FAULT_INJECTION_DEBUG_FS=y
-CONFIG_FAIL_FUNCTION=y
CONFIG_FAULT_INJECTION_STACKTRACE_FILTER=y
CONFIG_LKDTM=m
CONFIG_TEST_MIN_HEAP=y
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 2bc2d0fe5774..cec71268e3bc 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -181,7 +181,6 @@ CONFIG_NFT_CT=m
CONFIG_NFT_LOG=m
CONFIG_NFT_LIMIT=m
CONFIG_NFT_NAT=m
-CONFIG_NFT_OBJREF=m
CONFIG_NFT_REJECT=m
CONFIG_NFT_COMPAT=m
CONFIG_NFT_HASH=m
@@ -559,6 +558,7 @@ CONFIG_INPUT_EVDEV=y
# CONFIG_INPUT_MOUSE is not set
# CONFIG_SERIO is not set
CONFIG_LEGACY_PTY_COUNT=0
+# CONFIG_LEGACY_TIOCSTI is not set
CONFIG_VIRTIO_CONSOLE=m
CONFIG_HW_RANDOM_VIRTIO=m
CONFIG_HANGCHECK_TIMER=m
@@ -645,6 +645,7 @@ CONFIG_CONFIGFS_FS=m
CONFIG_ECRYPT_FS=m
CONFIG_CRAMFS=m
CONFIG_SQUASHFS=m
+CONFIG_SQUASHFS_CHOICE_DECOMP_BY_MOUNT=y
CONFIG_SQUASHFS_XATTR=y
CONFIG_SQUASHFS_LZ4=y
CONFIG_SQUASHFS_LZO=y
@@ -688,6 +689,7 @@ CONFIG_SECURITY_LOCKDOWN_LSM_EARLY=y
CONFIG_SECURITY_LANDLOCK=y
CONFIG_INTEGRITY_SIGNATURE=y
CONFIG_INTEGRITY_ASYMMETRIC_KEYS=y
+CONFIG_INTEGRITY_PLATFORM_KEYRING=y
CONFIG_IMA=y
CONFIG_IMA_DEFAULT_HASH_SHA256=y
CONFIG_IMA_WRITE_POLICY=y
@@ -766,6 +768,7 @@ CONFIG_ZCRYPT=m
CONFIG_PKEY=m
CONFIG_CRYPTO_PAES_S390=m
CONFIG_CRYPTO_DEV_VIRTIO=m
+CONFIG_SYSTEM_BLACKLIST_KEYRING=y
CONFIG_CORDIC=m
CONFIG_PRIME_NUMBERS=m
CONFIG_CRYPTO_LIB_CURVE25519=m
@@ -798,7 +801,6 @@ CONFIG_STACK_TRACER=y
CONFIG_SCHED_TRACER=y
CONFIG_FTRACE_SYSCALLS=y
CONFIG_BLK_DEV_IO_TRACE=y
-CONFIG_BPF_KPROBE_OVERRIDE=y
CONFIG_HIST_TRIGGERS=y
CONFIG_SAMPLES=y
CONFIG_SAMPLE_TRACE_PRINTK=m
diff --git a/arch/s390/configs/zfcpdump_defconfig b/arch/s390/configs/zfcpdump_defconfig
index ae14ab0b864d..a9c0c81d1de9 100644
--- a/arch/s390/configs/zfcpdump_defconfig
+++ b/arch/s390/configs/zfcpdump_defconfig
@@ -13,7 +13,6 @@ CONFIG_TUNE_ZEC12=y
# CONFIG_COMPAT is not set
CONFIG_NR_CPUS=2
CONFIG_HZ_100=y
-# CONFIG_RELOCATABLE is not set
# CONFIG_CHSC_SCH is not set
# CONFIG_SCM_BUS is not set
CONFIG_CRASH_DUMP=y
@@ -50,6 +49,7 @@ CONFIG_ZFCP=y
# CONFIG_INPUT_KEYBOARD is not set
# CONFIG_INPUT_MOUSE is not set
# CONFIG_SERIO is not set
+# CONFIG_LEGACY_TIOCSTI is not set
# CONFIG_HVC_IUCV is not set
# CONFIG_HW_RANDOM_S390 is not set
# CONFIG_HMC_DRV is not set
diff --git a/arch/s390/include/asm/cpu_mf.h b/arch/s390/include/asm/cpu_mf.h
index feaba12dbecb..efa103b52a1a 100644
--- a/arch/s390/include/asm/cpu_mf.h
+++ b/arch/s390/include/asm/cpu_mf.h
@@ -131,19 +131,21 @@ struct hws_combined_entry {
struct hws_diag_entry diag; /* Diagnostic-sampling data entry */
} __packed;

-struct hws_trailer_entry {
- union {
- struct {
- unsigned int f:1; /* 0 - Block Full Indicator */
- unsigned int a:1; /* 1 - Alert request control */
- unsigned int t:1; /* 2 - Timestamp format */
- unsigned int :29; /* 3 - 31: Reserved */
- unsigned int bsdes:16; /* 32-47: size of basic SDE */
- unsigned int dsdes:16; /* 48-63: size of diagnostic SDE */
- };
- unsigned long long flags; /* 0 - 63: All indicators */
+union hws_trailer_header {
+ struct {
+ unsigned int f:1; /* 0 - Block Full Indicator */
+ unsigned int a:1; /* 1 - Alert request control */
+ unsigned int t:1; /* 2 - Timestamp format */
+ unsigned int :29; /* 3 - 31: Reserved */
+ unsigned int bsdes:16; /* 32-47: size of basic SDE */
+ unsigned int dsdes:16; /* 48-63: size of diagnostic SDE */
+ unsigned long long overflow; /* 64 - Overflow Count */
};
- unsigned long long overflow; /* 64 - sample Overflow count */
+ __uint128_t val;
+};
+
+struct hws_trailer_entry {
+ union hws_trailer_header header; /* 0 - 15 Flags + Overflow Count */
unsigned char timestamp[16]; /* 16 - 31 timestamp */
unsigned long long reserved1; /* 32 -Reserved */
unsigned long long reserved2; /* */
@@ -290,14 +292,11 @@ static inline unsigned long sample_rate_to_freq(struct hws_qsi_info_block *qsi,
return USEC_PER_SEC * qsi->cpu_speed / rate;
}

-#define SDB_TE_ALERT_REQ_MASK 0x4000000000000000UL
-#define SDB_TE_BUFFER_FULL_MASK 0x8000000000000000UL
-
/* Return TOD timestamp contained in an trailer entry */
static inline unsigned long long trailer_timestamp(struct hws_trailer_entry *te)
{
/* TOD in STCKE format */
- if (te->t)
+ if (te->header.t)
return *((unsigned long long *) &te->timestamp[1]);

/* TOD in STCK format */
diff --git a/arch/s390/include/asm/debug.h b/arch/s390/include/asm/debug.h
index 77f24262c25c..ac665b9670c5 100644
--- a/arch/s390/include/asm/debug.h
+++ b/arch/s390/include/asm/debug.h
@@ -4,8 +4,8 @@
*
* Copyright IBM Corp. 1999, 2020
*/
-#ifndef DEBUG_H
-#define DEBUG_H
+#ifndef _ASM_S390_DEBUG_H
+#define _ASM_S390_DEBUG_H

#include <linux/string.h>
#include <linux/spinlock.h>
@@ -487,4 +487,4 @@ void debug_register_static(debug_info_t *id, int pages_per_area, int nr_areas);

#endif /* MODULE */

-#endif /* DEBUG_H */
+#endif /* _ASM_S390_DEBUG_H */
diff --git a/arch/s390/include/asm/percpu.h b/arch/s390/include/asm/percpu.h
index cb5fc0690435..081837b391e3 100644
--- a/arch/s390/include/asm/percpu.h
+++ b/arch/s390/include/asm/percpu.h
@@ -31,7 +31,7 @@
pcp_op_T__ *ptr__; \
preempt_disable_notrace(); \
ptr__ = raw_cpu_ptr(&(pcp)); \
- prev__ = *ptr__; \
+ prev__ = READ_ONCE(*ptr__); \
do { \
old__ = prev__; \
new__ = old__ op (val); \
diff --git a/arch/s390/kernel/machine_kexec_file.c b/arch/s390/kernel/machine_kexec_file.c
index fc6d5f58debe..2df94d32140c 100644
--- a/arch/s390/kernel/machine_kexec_file.c
+++ b/arch/s390/kernel/machine_kexec_file.c
@@ -187,8 +187,6 @@ static int kexec_file_add_ipl_report(struct kimage *image,

data->memsz = ALIGN(data->memsz, PAGE_SIZE);
buf.mem = data->memsz;
- if (image->type == KEXEC_TYPE_CRASH)
- buf.mem += crashk_res.start;

ptr = (void *)ipl_cert_list_addr;
end = ptr + ipl_cert_list_size;
@@ -225,6 +223,9 @@ static int kexec_file_add_ipl_report(struct kimage *image,
data->kernel_buf + offsetof(struct lowcore, ipl_parmblock_ptr);
*lc_ipl_parmblock_ptr = (__u32)buf.mem;

+ if (image->type == KEXEC_TYPE_CRASH)
+ buf.mem += crashk_res.start;
+
ret = kexec_add_buffer(&buf);
out:
return ret;
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index 332a49965130..ce886a03545a 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -163,14 +163,15 @@ static void free_sampling_buffer(struct sf_buffer *sfb)

static int alloc_sample_data_block(unsigned long *sdbt, gfp_t gfp_flags)
{
- unsigned long sdb, *trailer;
+ struct hws_trailer_entry *te;
+ unsigned long sdb;

/* Allocate and initialize sample-data-block */
sdb = get_zeroed_page(gfp_flags);
if (!sdb)
return -ENOMEM;
- trailer = trailer_entry_ptr(sdb);
- *trailer = SDB_TE_ALERT_REQ_MASK;
+ te = (struct hws_trailer_entry *)trailer_entry_ptr(sdb);
+ te->header.a = 1;

/* Link SDB into the sample-data-block-table */
*sdbt = sdb;
@@ -1206,7 +1207,7 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt,
"%s: Found unknown"
" sampling data entry: te->f %i"
" basic.def %#4x (%p)\n", __func__,
- te->f, sample->def, sample);
+ te->header.f, sample->def, sample);
/* Sample slot is not yet written or other record.
*
* This condition can occur if the buffer was reused
@@ -1217,7 +1218,7 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt,
* that are not full. Stop processing if the first
* invalid format was detected.
*/
- if (!te->f)
+ if (!te->header.f)
break;
}

@@ -1227,6 +1228,16 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt,
}
}

+static inline __uint128_t __cdsg(__uint128_t *ptr, __uint128_t old, __uint128_t new)
+{
+ asm volatile(
+ " cdsg %[old],%[new],%[ptr]\n"
+ : [old] "+d" (old), [ptr] "+QS" (*ptr)
+ : [new] "d" (new)
+ : "memory", "cc");
+ return old;
+}
+
/* hw_perf_event_update() - Process sampling buffer
* @event: The perf event
* @flush_all: Flag to also flush partially filled sample-data-blocks
@@ -1243,10 +1254,11 @@ static void hw_collect_samples(struct perf_event *event, unsigned long *sdbt,
*/
static void hw_perf_event_update(struct perf_event *event, int flush_all)
{
+ unsigned long long event_overflow, sampl_overflow, num_sdb;
+ union hws_trailer_header old, prev, new;
struct hw_perf_event *hwc = &event->hw;
struct hws_trailer_entry *te;
unsigned long *sdbt;
- unsigned long long event_overflow, sampl_overflow, num_sdb, te_flags;
int done;

/*
@@ -1266,25 +1278,25 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all)
te = (struct hws_trailer_entry *) trailer_entry_ptr(*sdbt);

/* Leave loop if no more work to do (block full indicator) */
- if (!te->f) {
+ if (!te->header.f) {
done = 1;
if (!flush_all)
break;
}

/* Check the sample overflow count */
- if (te->overflow)
+ if (te->header.overflow)
/* Account sample overflows and, if a particular limit
* is reached, extend the sampling buffer.
* For details, see sfb_account_overflows().
*/
- sampl_overflow += te->overflow;
+ sampl_overflow += te->header.overflow;

/* Timestamps are valid for full sample-data-blocks only */
debug_sprintf_event(sfdbg, 6, "%s: sdbt %#lx "
"overflow %llu timestamp %#llx\n",
- __func__, (unsigned long)sdbt, te->overflow,
- (te->f) ? trailer_timestamp(te) : 0ULL);
+ __func__, (unsigned long)sdbt, te->header.overflow,
+ (te->header.f) ? trailer_timestamp(te) : 0ULL);

/* Collect all samples from a single sample-data-block and
* flag if an (perf) event overflow happened. If so, the PMU
@@ -1294,12 +1306,16 @@ static void hw_perf_event_update(struct perf_event *event, int flush_all)
num_sdb++;

/* Reset trailer (using compare-double-and-swap) */
+ /* READ_ONCE() 16 byte header */
+ prev.val = __cdsg(&te->header.val, 0, 0);
do {
- te_flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK;
- te_flags |= SDB_TE_ALERT_REQ_MASK;
- } while (!cmpxchg_double(&te->flags, &te->overflow,
- te->flags, te->overflow,
- te_flags, 0ULL));
+ old.val = prev.val;
+ new.val = prev.val;
+ new.f = 0;
+ new.a = 1;
+ new.overflow = 0;
+ prev.val = __cdsg(&te->header.val, old.val, new.val);
+ } while (prev.val != old.val);

/* Advance to next sample-data-block */
sdbt++;
@@ -1384,7 +1400,7 @@ static void aux_output_end(struct perf_output_handle *handle)
range_scan = AUX_SDB_NUM_ALERT(aux);
for (i = 0, idx = aux->head; i < range_scan; i++, idx++) {
te = aux_sdb_trailer(aux, idx);
- if (!(te->flags & SDB_TE_BUFFER_FULL_MASK))
+ if (!te->header.f)
break;
}
/* i is num of SDBs which are full */
@@ -1392,7 +1408,7 @@ static void aux_output_end(struct perf_output_handle *handle)

/* Remove alert indicators in the buffer */
te = aux_sdb_trailer(aux, aux->alert_mark);
- te->flags &= ~SDB_TE_ALERT_REQ_MASK;
+ te->header.a = 0;

debug_sprintf_event(sfdbg, 6, "%s: SDBs %ld range %ld head %ld\n",
__func__, i, range_scan, aux->head);
@@ -1437,9 +1453,9 @@ static int aux_output_begin(struct perf_output_handle *handle,
idx = aux->empty_mark + 1;
for (i = 0; i < range_scan; i++, idx++) {
te = aux_sdb_trailer(aux, idx);
- te->flags &= ~(SDB_TE_BUFFER_FULL_MASK |
- SDB_TE_ALERT_REQ_MASK);
- te->overflow = 0;
+ te->header.f = 0;
+ te->header.a = 0;
+ te->header.overflow = 0;
}
/* Save the position of empty SDBs */
aux->empty_mark = aux->head + range - 1;
@@ -1448,7 +1464,7 @@ static int aux_output_begin(struct perf_output_handle *handle,
/* Set alert indicator */
aux->alert_mark = aux->head + range/2 - 1;
te = aux_sdb_trailer(aux, aux->alert_mark);
- te->flags = te->flags | SDB_TE_ALERT_REQ_MASK;
+ te->header.a = 1;

/* Reset hardware buffer head */
head = AUX_SDB_INDEX(aux, aux->head);
@@ -1475,14 +1491,17 @@ static int aux_output_begin(struct perf_output_handle *handle,
static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index,
unsigned long long *overflow)
{
- unsigned long long orig_overflow, orig_flags, new_flags;
+ union hws_trailer_header old, prev, new;
struct hws_trailer_entry *te;

te = aux_sdb_trailer(aux, alert_index);
+ /* READ_ONCE() 16 byte header */
+ prev.val = __cdsg(&te->header.val, 0, 0);
do {
- orig_flags = te->flags;
- *overflow = orig_overflow = te->overflow;
- if (orig_flags & SDB_TE_BUFFER_FULL_MASK) {
+ old.val = prev.val;
+ new.val = prev.val;
+ *overflow = old.overflow;
+ if (old.f) {
/*
* SDB is already set by hardware.
* Abort and try to set somewhere
@@ -1490,10 +1509,10 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index,
*/
return false;
}
- new_flags = orig_flags | SDB_TE_ALERT_REQ_MASK;
- } while (!cmpxchg_double(&te->flags, &te->overflow,
- orig_flags, orig_overflow,
- new_flags, 0ULL));
+ new.a = 1;
+ new.overflow = 0;
+ prev.val = __cdsg(&te->header.val, old.val, new.val);
+ } while (prev.val != old.val);
return true;
}

@@ -1522,8 +1541,9 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index,
static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range,
unsigned long long *overflow)
{
- unsigned long long orig_overflow, orig_flags, new_flags;
unsigned long i, range_scan, idx, idx_old;
+ union hws_trailer_header old, prev, new;
+ unsigned long long orig_overflow;
struct hws_trailer_entry *te;

debug_sprintf_event(sfdbg, 6, "%s: range %ld head %ld alert %ld "
@@ -1554,17 +1574,20 @@ static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range,
idx_old = idx = aux->empty_mark + 1;
for (i = 0; i < range_scan; i++, idx++) {
te = aux_sdb_trailer(aux, idx);
+ /* READ_ONCE() 16 byte header */
+ prev.val = __cdsg(&te->header.val, 0, 0);
do {
- orig_flags = te->flags;
- orig_overflow = te->overflow;
- new_flags = orig_flags & ~SDB_TE_BUFFER_FULL_MASK;
+ old.val = prev.val;
+ new.val = prev.val;
+ orig_overflow = old.overflow;
+ new.f = 0;
+ new.overflow = 0;
if (idx == aux->alert_mark)
- new_flags |= SDB_TE_ALERT_REQ_MASK;
+ new.a = 1;
else
- new_flags &= ~SDB_TE_ALERT_REQ_MASK;
- } while (!cmpxchg_double(&te->flags, &te->overflow,
- orig_flags, orig_overflow,
- new_flags, 0ULL));
+ new.a = 0;
+ prev.val = __cdsg(&te->header.val, old.val, new.val);
+ } while (prev.val != old.val);
*overflow += orig_overflow;
}

diff --git a/arch/s390/kernel/vmlinux.lds.S b/arch/s390/kernel/vmlinux.lds.S
index 5ea3830af0cc..cbf9c1b0beda 100644
--- a/arch/s390/kernel/vmlinux.lds.S
+++ b/arch/s390/kernel/vmlinux.lds.S
@@ -17,6 +17,8 @@
/* Handle ro_after_init data on our own. */
#define RO_AFTER_INIT_DATA

+#define RUNTIME_DISCARD_EXIT
+
#define EMITS_PT_NOTE

#include <asm-generic/vmlinux.lds.h>
@@ -79,6 +81,7 @@ SECTIONS
_end_amode31_refs = .;
}

+ . = ALIGN(PAGE_SIZE);
_edata = .; /* End of data section */

/* will be freed after init */
@@ -193,6 +196,7 @@ SECTIONS

BSS_SECTION(PAGE_SIZE, 4 * PAGE_SIZE, PAGE_SIZE)

+ . = ALIGN(PAGE_SIZE);
_end = . ;

/*
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 1dae78deddf2..ab26aa53ee37 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -83,8 +83,9 @@ static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id)
struct esca_block *sca = vcpu->kvm->arch.sca;
union esca_sigp_ctrl *sigp_ctrl =
&(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
- union esca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl;
+ union esca_sigp_ctrl new_val = {0}, old_val;

+ old_val = READ_ONCE(*sigp_ctrl);
new_val.scn = src_id;
new_val.c = 1;
old_val.c = 0;
@@ -95,8 +96,9 @@ static int sca_inject_ext_call(struct kvm_vcpu *vcpu, int src_id)
struct bsca_block *sca = vcpu->kvm->arch.sca;
union bsca_sigp_ctrl *sigp_ctrl =
&(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
- union bsca_sigp_ctrl new_val = {0}, old_val = *sigp_ctrl;
+ union bsca_sigp_ctrl new_val = {0}, old_val;

+ old_val = READ_ONCE(*sigp_ctrl);
new_val.scn = src_id;
new_val.c = 1;
old_val.c = 0;
@@ -126,16 +128,18 @@ static void sca_clear_ext_call(struct kvm_vcpu *vcpu)
struct esca_block *sca = vcpu->kvm->arch.sca;
union esca_sigp_ctrl *sigp_ctrl =
&(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
- union esca_sigp_ctrl old = *sigp_ctrl;
+ union esca_sigp_ctrl old;

+ old = READ_ONCE(*sigp_ctrl);
expect = old.value;
rc = cmpxchg(&sigp_ctrl->value, old.value, 0);
} else {
struct bsca_block *sca = vcpu->kvm->arch.sca;
union bsca_sigp_ctrl *sigp_ctrl =
&(sca->cpu[vcpu->vcpu_id].sigp_ctrl);
- union bsca_sigp_ctrl old = *sigp_ctrl;
+ union bsca_sigp_ctrl old;

+ old = READ_ONCE(*sigp_ctrl);
expect = old.value;
rc = cmpxchg(&sigp_ctrl->value, old.value, 0);
}