[GIT PULL] s390 patches for the 5.6 merge window

From: Vasily Gorbik
Date: Tue Jan 28 2020 - 11:54:22 EST

Hello Linus,

please pull s390 fixes and features for 5.6.

Thank you,
Vasily

The following changes since commit d1eef1c619749b2a57e514a3fa67d9a516ffa919:

Linux 5.5-rc2 (2019-12-15 15:16:08 -0800)

are available in the Git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git tags/s390-5.6-1

for you to fetch changes up to 17248ea0367465f4aaef728f6af661ed38e38cf1:

s390: fix __EMIT_BUG() macro (2020-01-22 13:05:35 +0100)

----------------------------------------------------------------
s390 updates for the 5.6 merge window

- Add clang 10 build support.

- Fix BUG() implementation to contain precise bug address, which is
relevant for kprobes.

- Make ftraced function appear in a stacktrace.

- Minor perf improvements and refactoring.

- Possible deadlock and recovery fixes in pci code.

----------------------------------------------------------------
Niklas Schnelle (2):
s390/pci: Recover handle in clp_set_pci_fn()
s390/pci: Fix possible deadlock in recover_store()

Sven Schnelle (1):
s390: fix __EMIT_BUG() macro

Thomas Richter (3):
s390/cpum_sf: Convert debug trace to common layout
s390/cpum_sf: Use kzalloc and minor changes
s390/cpum_sf: Use DIV_ROUND_UP

Vasily Gorbik (3):
s390/jump_label: use "i" constraint for clang
s390: adjust -mpacked-stack support check for clang 10
s390/ftrace: generate traced function stack frame

arch/s390/Makefile | 2 +-
arch/s390/boot/head.S | 2 +-
arch/s390/include/asm/bug.h | 16 ++++-----
arch/s390/include/asm/jump_label.h | 4 ++-
arch/s390/include/asm/pci.h | 2 +-
arch/s390/kernel/entry.h | 1 +
arch/s390/kernel/mcount.S | 15 ++++++++-
arch/s390/kernel/perf_cpum_sf.c | 67 ++++++++++++++++++++------------------
arch/s390/kernel/pgm_check.S | 2 +-
arch/s390/kernel/traps.c | 41 ++++++++++++++++++++---
arch/s390/pci/pci.c | 2 +-
arch/s390/pci/pci_clp.c | 48 ++++++++++++++++-----------
arch/s390/pci/pci_sysfs.c | 63 +++++++++++++++++++++++------------
13 files changed, 172 insertions(+), 93 deletions(-)

diff --git a/arch/s390/Makefile b/arch/s390/Makefile
index ba8556bb0fb1..e0e3a465bbfd 100644
--- a/arch/s390/Makefile
+++ b/arch/s390/Makefile
@@ -69,7 +69,7 @@ cflags-y += -Wa,-I$(srctree)/arch/$(ARCH)/include
#
cflags-$(CONFIG_FRAME_POINTER) += -fno-optimize-sibling-calls

-ifeq ($(call cc-option-yn,-mpacked-stack),y)
+ifeq ($(call cc-option-yn,-mpacked-stack -mbackchain -msoft-float),y)
cflags-$(CONFIG_PACK_STACK) += -mpacked-stack -D__PACK_STACK
aflags-$(CONFIG_PACK_STACK) += -D__PACK_STACK
endif
diff --git a/arch/s390/boot/head.S b/arch/s390/boot/head.S
index 4b86a8d3c121..dae10961d072 100644
--- a/arch/s390/boot/head.S
+++ b/arch/s390/boot/head.S
@@ -329,7 +329,7 @@ ENTRY(startup_kdump)
.quad .Lduct # cr5: primary-aste origin
.quad 0 # cr6: I/O interrupts
.quad 0 # cr7: secondary space segment table
- .quad 0 # cr8: access registers translation
+ .quad 0x0000000000008000 # cr8: access registers translation
.quad 0 # cr9: tracing off
.quad 0 # cr10: tracing off
.quad 0 # cr11: tracing off
diff --git a/arch/s390/include/asm/bug.h b/arch/s390/include/asm/bug.h
index a2b11ac00f60..7725f8006fdf 100644
--- a/arch/s390/include/asm/bug.h
+++ b/arch/s390/include/asm/bug.h
@@ -10,15 +10,14 @@

#define __EMIT_BUG(x) do { \
asm_inline volatile( \
- "0: j 0b+2\n" \
- "1:\n" \
+ "0: mc 0,0\n" \
".section .rodata.str,\"aMS\",@progbits,1\n" \
- "2: .asciz \""__FILE__"\"\n" \
+ "1: .asciz \""__FILE__"\"\n" \
".previous\n" \
".section __bug_table,\"awM\",@progbits,%2\n" \
- "3: .long 1b-3b,2b-3b\n" \
+ "2: .long 0b-2b,1b-2b\n" \
" .short %0,%1\n" \
- " .org 3b+%2\n" \
+ " .org 2b+%2\n" \
".previous\n" \
: : "i" (__LINE__), \
"i" (x), \
@@ -29,12 +28,11 @@

#define __EMIT_BUG(x) do { \
asm_inline volatile( \
- "0: j 0b+2\n" \
- "1:\n" \
+ "0: mc 0,0\n" \
".section __bug_table,\"awM\",@progbits,%1\n" \
- "2: .long 1b-2b\n" \
+ "1: .long 0b-1b\n" \
" .short %0\n" \
- " .org 2b+%1\n" \
+ " .org 1b+%1\n" \
".previous\n" \
: : "i" (x), \
"i" (sizeof(struct bug_entry))); \
diff --git a/arch/s390/include/asm/jump_label.h b/arch/s390/include/asm/jump_label.h
index 39f747d63758..dcb1bba4f406 100644
--- a/arch/s390/include/asm/jump_label.h
+++ b/arch/s390/include/asm/jump_label.h
@@ -10,7 +10,9 @@
#define JUMP_LABEL_NOP_SIZE 6
#define JUMP_LABEL_NOP_OFFSET 2

-#if __GNUC__ < 9
+#ifdef CONFIG_CC_IS_CLANG
+#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "i"
+#elif __GNUC__ < 9
#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "X"
#else
#define JUMP_LABEL_STATIC_KEY_CONSTRAINT "jdd"
diff --git a/arch/s390/include/asm/pci.h b/arch/s390/include/asm/pci.h
index 3a06c264ea53..b05187ce5dbd 100644
--- a/arch/s390/include/asm/pci.h
+++ b/arch/s390/include/asm/pci.h
@@ -180,7 +180,7 @@ void zpci_remove_reserved_devices(void);
/* CLP */
int clp_scan_pci_devices(void);
int clp_rescan_pci_devices(void);
-int clp_rescan_pci_devices_simple(void);
+int clp_rescan_pci_devices_simple(u32 *fid);
int clp_add_pci_device(u32, u32, int);
int clp_enable_fh(struct zpci_dev *, u8);
int clp_disable_fh(struct zpci_dev *);
diff --git a/arch/s390/kernel/entry.h b/arch/s390/kernel/entry.h
index b2956d49b6ad..1d3927e01a5f 100644
--- a/arch/s390/kernel/entry.h
+++ b/arch/s390/kernel/entry.h
@@ -45,6 +45,7 @@ void specification_exception(struct pt_regs *regs);
void transaction_exception(struct pt_regs *regs);
void translation_exception(struct pt_regs *regs);
void vector_exception(struct pt_regs *regs);
+void monitor_event_exception(struct pt_regs *regs);

void do_per_trap(struct pt_regs *regs);
void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str);
diff --git a/arch/s390/kernel/mcount.S b/arch/s390/kernel/mcount.S
index 9e1660a6b9db..3431b2d5e334 100644
--- a/arch/s390/kernel/mcount.S
+++ b/arch/s390/kernel/mcount.S
@@ -26,6 +26,12 @@ ENDPROC(ftrace_stub)
#define STACK_PTREGS (STACK_FRAME_OVERHEAD)
#define STACK_PTREGS_GPRS (STACK_PTREGS + __PT_GPRS)
#define STACK_PTREGS_PSW (STACK_PTREGS + __PT_PSW)
+#ifdef __PACK_STACK
+/* allocate just enough for r14, r15 and backchain */
+#define TRACED_FUNC_FRAME_SIZE 24
+#else
+#define TRACED_FUNC_FRAME_SIZE STACK_FRAME_OVERHEAD
+#endif

ENTRY(_mcount)
BR_EX %r14
@@ -39,9 +45,16 @@ ENTRY(ftrace_caller)
#if !(defined(CC_USING_HOTPATCH) || defined(CC_USING_NOP_MCOUNT))
aghi %r0,MCOUNT_RETURN_FIXUP
#endif
- aghi %r15,-STACK_FRAME_SIZE
+ # allocate stack frame for ftrace_caller to contain traced function
+ aghi %r15,-TRACED_FUNC_FRAME_SIZE
stg %r1,__SF_BACKCHAIN(%r15)
+ stg %r0,(__SF_GPRS+8*8)(%r15)
+ stg %r15,(__SF_GPRS+9*8)(%r15)
+ # allocate pt_regs and stack frame for ftrace_trace_function
+ aghi %r15,-STACK_FRAME_SIZE
stg %r1,(STACK_PTREGS_GPRS+15*8)(%r15)
+ aghi %r1,-TRACED_FUNC_FRAME_SIZE
+ stg %r1,__SF_BACKCHAIN(%r15)
stg %r0,(STACK_PTREGS_PSW+8)(%r15)
stmg %r2,%r14,(STACK_PTREGS_GPRS+2*8)(%r15)
#ifdef CONFIG_HAVE_MARCH_Z196_FEATURES
diff --git a/arch/s390/kernel/perf_cpum_sf.c b/arch/s390/kernel/perf_cpum_sf.c
index 77d93c534284..b095b1c78987 100644
--- a/arch/s390/kernel/perf_cpum_sf.c
+++ b/arch/s390/kernel/perf_cpum_sf.c
@@ -1383,7 +1383,8 @@ static void aux_output_end(struct perf_output_handle *handle)
te = aux_sdb_trailer(aux, aux->alert_mark);
te->flags &= ~SDB_TE_ALERT_REQ_MASK;

- debug_sprintf_event(sfdbg, 6, "%s: collect %#lx SDBs\n", __func__, i);
+ debug_sprintf_event(sfdbg, 6, "%s: SDBs %ld range %ld head %ld\n",
+ __func__, i, range_scan, aux->head);
}

/*
@@ -1416,13 +1417,17 @@ static int aux_output_begin(struct perf_output_handle *handle,
* SDBs between aux->head and aux->empty_mark are already ready
* for new data. range_scan is num of SDBs not within them.
*/
+ debug_sprintf_event(sfdbg, 6,
+ "%s: range %ld head %ld alert %ld empty %ld\n",
+ __func__, range, aux->head, aux->alert_mark,
+ aux->empty_mark);
if (range > AUX_SDB_NUM_EMPTY(aux)) {
range_scan = range - AUX_SDB_NUM_EMPTY(aux);
idx = aux->empty_mark + 1;
for (i = 0; i < range_scan; i++, idx++) {
te = aux_sdb_trailer(aux, idx);
- te->flags = te->flags & ~SDB_TE_BUFFER_FULL_MASK;
- te->flags = te->flags & ~SDB_TE_ALERT_REQ_MASK;
+ te->flags &= ~(SDB_TE_BUFFER_FULL_MASK |
+ SDB_TE_ALERT_REQ_MASK);
te->overflow = 0;
}
/* Save the position of empty SDBs */
@@ -1441,15 +1446,11 @@ static int aux_output_begin(struct perf_output_handle *handle,
cpuhw->lsctl.tear = base + offset * sizeof(unsigned long);
cpuhw->lsctl.dear = aux->sdb_index[head];

- debug_sprintf_event(sfdbg, 6, "%s: "
- "head->alert_mark->empty_mark (num_alert, range)"
- "[%#lx -> %#lx -> %#lx] (%#lx, %#lx) "
- "tear index %#lx, tear %#lx dear %#lx\n", __func__,
+ debug_sprintf_event(sfdbg, 6, "%s: head %ld alert %ld empty %ld "
+ "index %ld tear %#lx dear %#lx\n", __func__,
aux->head, aux->alert_mark, aux->empty_mark,
- AUX_SDB_NUM_ALERT(aux), range,
head / CPUM_SF_SDB_PER_TABLE,
- cpuhw->lsctl.tear,
- cpuhw->lsctl.dear);
+ cpuhw->lsctl.tear, cpuhw->lsctl.dear);

return 0;
}
@@ -1469,8 +1470,7 @@ static bool aux_set_alert(struct aux_buffer *aux, unsigned long alert_index,
te = aux_sdb_trailer(aux, alert_index);
do {
orig_flags = te->flags;
- orig_overflow = te->overflow;
- *overflow = orig_overflow;
+ *overflow = orig_overflow = te->overflow;
if (orig_flags & SDB_TE_BUFFER_FULL_MASK) {
/*
* SDB is already set by hardware.
@@ -1512,9 +1512,12 @@ 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;
+ unsigned long i, range_scan, idx, idx_old;
struct hws_trailer_entry *te;

+ debug_sprintf_event(sfdbg, 6, "%s: range %ld head %ld alert %ld "
+ "empty %ld\n", __func__, range, aux->head,
+ aux->alert_mark, aux->empty_mark);
if (range <= AUX_SDB_NUM_EMPTY(aux))
/*
* No need to scan. All SDBs in range are marked as empty.
@@ -1537,7 +1540,7 @@ static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range,
* indicator fall into this range, set it.
*/
range_scan = range - AUX_SDB_NUM_EMPTY(aux);
- idx = aux->empty_mark + 1;
+ idx_old = idx = aux->empty_mark + 1;
for (i = 0; i < range_scan; i++, idx++) {
te = aux_sdb_trailer(aux, idx);
do {
@@ -1557,6 +1560,9 @@ static bool aux_reset_buffer(struct aux_buffer *aux, unsigned long range,
/* Update empty_mark to new position */
aux->empty_mark = aux->head + range - 1;

+ debug_sprintf_event(sfdbg, 6, "%s: range_scan %ld idx %ld..%ld "
+ "empty %ld\n", __func__, range_scan, idx_old,
+ idx - 1, aux->empty_mark);
return true;
}

@@ -1570,7 +1576,6 @@ static void hw_collect_aux(struct cpu_hw_sf *cpuhw)
unsigned long range = 0, size;
unsigned long long overflow = 0;
struct perf_output_handle *handle = &cpuhw->handle;
- unsigned long num_sdb;

aux = perf_get_aux(handle);
if (WARN_ON_ONCE(!aux))
@@ -1578,8 +1583,9 @@ static void hw_collect_aux(struct cpu_hw_sf *cpuhw)

/* Inform user space new data arrived */
size = AUX_SDB_NUM_ALERT(aux) << PAGE_SHIFT;
+ debug_sprintf_event(sfdbg, 6, "%s: #alert %ld\n", __func__,
+ size >> PAGE_SHIFT);
perf_aux_output_end(handle, size);
- num_sdb = aux->sfb.num_sdb;

while (!done) {
/* Get an output handle */
@@ -1587,7 +1593,7 @@ static void hw_collect_aux(struct cpu_hw_sf *cpuhw)
if (handle->size == 0) {
pr_err("The AUX buffer with %lu pages for the "
"diagnostic-sampling mode is full\n",
- num_sdb);
+ aux->sfb.num_sdb);
debug_sprintf_event(sfdbg, 1,
"%s: AUX buffer used up\n",
__func__);
@@ -1612,14 +1618,14 @@ static void hw_collect_aux(struct cpu_hw_sf *cpuhw)
size = range << PAGE_SHIFT;
perf_aux_output_end(&cpuhw->handle, size);
pr_err("Sample data caused the AUX buffer with %lu "
- "pages to overflow\n", num_sdb);
- debug_sprintf_event(sfdbg, 1, "%s: head %#lx range %#lx "
- "overflow %#llx\n", __func__,
+ "pages to overflow\n", aux->sfb.num_sdb);
+ debug_sprintf_event(sfdbg, 1, "%s: head %ld range %ld "
+ "overflow %lld\n", __func__,
aux->head, range, overflow);
} else {
size = AUX_SDB_NUM_ALERT(aux) << PAGE_SHIFT;
perf_aux_output_end(&cpuhw->handle, size);
- debug_sprintf_event(sfdbg, 6, "%s: head %#lx alert %#lx "
+ debug_sprintf_event(sfdbg, 6, "%s: head %ld alert %ld "
"already full, try another\n",
__func__,
aux->head, aux->alert_mark);
@@ -1627,11 +1633,9 @@ static void hw_collect_aux(struct cpu_hw_sf *cpuhw)
}

if (done)
- debug_sprintf_event(sfdbg, 6, "%s: aux_reset_buffer "
- "[%#lx -> %#lx -> %#lx] (%#lx, %#lx)\n",
- __func__, aux->head, aux->alert_mark,
- aux->empty_mark, AUX_SDB_NUM_ALERT(aux),
- range);
+ debug_sprintf_event(sfdbg, 6, "%s: head %ld alert %ld "
+ "empty %ld\n", __func__, aux->head,
+ aux->alert_mark, aux->empty_mark);
}

/*
@@ -1654,8 +1658,7 @@ static void aux_buffer_free(void *data)
kfree(aux->sdb_index);
kfree(aux);

- debug_sprintf_event(sfdbg, 4, "%s: free "
- "%lu SDBTs\n", __func__, num_sdbt);
+ debug_sprintf_event(sfdbg, 4, "%s: SDBTs %lu\n", __func__, num_sdbt);
}

static void aux_sdb_init(unsigned long sdb)
@@ -1707,13 +1710,13 @@ static void *aux_buffer_setup(struct perf_event *event, void **pages,
}

/* Allocate aux_buffer struct for the event */
- aux = kmalloc(sizeof(struct aux_buffer), GFP_KERNEL);
+ aux = kzalloc(sizeof(struct aux_buffer), GFP_KERNEL);
if (!aux)
goto no_aux;
sfb = &aux->sfb;

/* Allocate sdbt_index for fast reference */
- n_sdbt = (nr_pages + CPUM_SF_SDB_PER_TABLE - 1) / CPUM_SF_SDB_PER_TABLE;
+ n_sdbt = DIV_ROUND_UP(nr_pages, CPUM_SF_SDB_PER_TABLE);
aux->sdbt_index = kmalloc_array(n_sdbt, sizeof(void *), GFP_KERNEL);
if (!aux->sdbt_index)
goto no_sdbt_index;
@@ -1763,8 +1766,8 @@ static void *aux_buffer_setup(struct perf_event *event, void **pages,
*/
aux->empty_mark = sfb->num_sdb - 1;

- debug_sprintf_event(sfdbg, 4, "%s: setup %lu SDBTs and %lu SDBs\n",
- __func__, sfb->num_sdbt, sfb->num_sdb);
+ debug_sprintf_event(sfdbg, 4, "%s: SDBTs %lu SDBs %lu\n", __func__,
+ sfb->num_sdbt, sfb->num_sdb);

return aux;

diff --git a/arch/s390/kernel/pgm_check.S b/arch/s390/kernel/pgm_check.S
index 59dee9d3bebf..eee3a482195a 100644
--- a/arch/s390/kernel/pgm_check.S
+++ b/arch/s390/kernel/pgm_check.S
@@ -81,7 +81,7 @@ PGM_CHECK_DEFAULT /* 3c */
PGM_CHECK_DEFAULT /* 3d */
PGM_CHECK_DEFAULT /* 3e */
PGM_CHECK_DEFAULT /* 3f */
-PGM_CHECK_DEFAULT /* 40 */
+PGM_CHECK(monitor_event_exception) /* 40 */
PGM_CHECK_DEFAULT /* 41 */
PGM_CHECK_DEFAULT /* 42 */
PGM_CHECK_DEFAULT /* 43 */
diff --git a/arch/s390/kernel/traps.c b/arch/s390/kernel/traps.c
index 164c0282b41a..dc75588d7894 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -53,11 +53,6 @@ void do_report_trap(struct pt_regs *regs, int si_signo, int si_code, char *str)
if (fixup)
regs->psw.addr = extable_fixup(fixup);
else {
- enum bug_trap_type btt;
-
- btt = report_bug(regs->psw.addr, regs);
- if (btt == BUG_TRAP_TYPE_WARN)
- return;
die(regs, str);
}
}
@@ -245,6 +240,27 @@ void space_switch_exception(struct pt_regs *regs)
do_trap(regs, SIGILL, ILL_PRVOPC, "space switch event");
}

+void monitor_event_exception(struct pt_regs *regs)
+{
+ const struct exception_table_entry *fixup;
+
+ if (user_mode(regs))
+ return;
+
+ switch (report_bug(regs->psw.addr - (regs->int_code >> 16), regs)) {
+ case BUG_TRAP_TYPE_NONE:
+ fixup = s390_search_extables(regs->psw.addr);
+ if (fixup)
+ regs->psw.addr = extable_fixup(fixup);
+ break;
+ case BUG_TRAP_TYPE_WARN:
+ break;
+ case BUG_TRAP_TYPE_BUG:
+ die(regs, "monitor event");
+ break;
+ }
+}
+
void kernel_stack_overflow(struct pt_regs *regs)
{
bust_spinlocks(1);
@@ -255,8 +271,23 @@ void kernel_stack_overflow(struct pt_regs *regs)
}
NOKPROBE_SYMBOL(kernel_stack_overflow);

+static void test_monitor_call(void)
+{
+ int val = 1;
+
+ asm volatile(
+ " mc 0,0\n"
+ "0: xgr %0,%0\n"
+ "1:\n"
+ EX_TABLE(0b,1b)
+ : "+d" (val));
+ if (!val)
+ panic("Monitor call doesn't work!\n");
+}
+
void __init trap_init(void)
{
sort_extable(__start_dma_ex_table, __stop_dma_ex_table);
local_mcck_enable();
+ test_monitor_call();
}
diff --git a/arch/s390/pci/pci.c b/arch/s390/pci/pci.c
index 8e872951c07b..bc61ea18e88d 100644
--- a/arch/s390/pci/pci.c
+++ b/arch/s390/pci/pci.c
@@ -939,5 +939,5 @@ subsys_initcall_sync(pci_base_init);
void zpci_rescan(void)
{
if (zpci_is_enabled())
- clp_rescan_pci_devices_simple();
+ clp_rescan_pci_devices_simple(NULL);
}
diff --git a/arch/s390/pci/pci_clp.c b/arch/s390/pci/pci_clp.c
index 4c613e569fe0..0d3d8f170ea4 100644
--- a/arch/s390/pci/pci_clp.c
+++ b/arch/s390/pci/pci_clp.c
@@ -240,12 +240,14 @@ int clp_add_pci_device(u32 fid, u32 fh, int configured)
}

/*
- * Enable/Disable a given PCI function defined by its function handle.
+ * Enable/Disable a given PCI function and update its function handle if
+ * necessary
*/
-static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
+static int clp_set_pci_fn(struct zpci_dev *zdev, u8 nr_dma_as, u8 command)
{
struct clp_req_rsp_set_pci *rrb;
int rc, retries = 100;
+ u32 fid = zdev->fid;

rrb = clp_alloc_block(GFP_KERNEL);
if (!rrb)
@@ -256,7 +258,7 @@ static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
rrb->request.hdr.len = sizeof(rrb->request);
rrb->request.hdr.cmd = CLP_SET_PCI_FN;
rrb->response.hdr.len = sizeof(rrb->response);
- rrb->request.fh = *fh;
+ rrb->request.fh = zdev->fh;
rrb->request.oc = command;
rrb->request.ndas = nr_dma_as;

@@ -269,12 +271,17 @@ static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)
}
} while (rrb->response.hdr.rsp == CLP_RC_SETPCIFN_BUSY);

- if (!rc && rrb->response.hdr.rsp == CLP_RC_OK)
- *fh = rrb->response.fh;
- else {
+ if (rc || rrb->response.hdr.rsp != CLP_RC_OK) {
zpci_err("Set PCI FN:\n");
zpci_err_clp(rrb->response.hdr.rsp, rc);
- rc = -EIO;
+ }
+
+ if (!rc && rrb->response.hdr.rsp == CLP_RC_OK) {
+ zdev->fh = rrb->response.fh;
+ } else if (!rc && rrb->response.hdr.rsp == CLP_RC_SETPCIFN_ALRDY &&
+ rrb->response.fh == 0) {
+ /* Function is already in desired state - update handle */
+ rc = clp_rescan_pci_devices_simple(&fid);
}
clp_free_block(rrb);
return rc;
@@ -282,18 +289,17 @@ static int clp_set_pci_fn(u32 *fh, u8 nr_dma_as, u8 command)

int clp_enable_fh(struct zpci_dev *zdev, u8 nr_dma_as)
{
- u32 fh = zdev->fh;
int rc;

- rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
- zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
+ rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_PCI_FN);
+ zpci_dbg(3, "ena fid:%x, fh:%x, rc:%d\n", zdev->fid, zdev->fh, rc);
if (rc)
goto out;

- zdev->fh = fh;
if (zpci_use_mio(zdev)) {
- rc = clp_set_pci_fn(&fh, nr_dma_as, CLP_SET_ENABLE_MIO);
- zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
+ rc = clp_set_pci_fn(zdev, nr_dma_as, CLP_SET_ENABLE_MIO);
+ zpci_dbg(3, "ena mio fid:%x, fh:%x, rc:%d\n",
+ zdev->fid, zdev->fh, rc);
if (rc)
clp_disable_fh(zdev);
}
@@ -309,11 +315,8 @@ int clp_disable_fh(struct zpci_dev *zdev)
if (!zdev_enabled(zdev))
return 0;

- rc = clp_set_pci_fn(&fh, 0, CLP_SET_DISABLE_PCI_FN);
+ rc = clp_set_pci_fn(zdev, 0, CLP_SET_DISABLE_PCI_FN);
zpci_dbg(3, "dis fid:%x, fh:%x, rc:%d\n", zdev->fid, fh, rc);
- if (!rc)
- zdev->fh = fh;
-
return rc;
}

@@ -370,10 +373,14 @@ static void __clp_add(struct clp_fh_list_entry *entry, void *data)
static void __clp_update(struct clp_fh_list_entry *entry, void *data)
{
struct zpci_dev *zdev;
+ u32 *fid = data;

if (!entry->vendor_id)
return;

+ if (fid && *fid != entry->fid)
+ return;
+
zdev = get_zdev_by_fid(entry->fid);
if (!zdev)
return;
@@ -413,7 +420,10 @@ int clp_rescan_pci_devices(void)
return rc;
}

-int clp_rescan_pci_devices_simple(void)
+/* Rescan PCI functions and refresh function handles. If fid is non-NULL only
+ * refresh the handle of the function matching @fid
+ */
+int clp_rescan_pci_devices_simple(u32 *fid)
{
struct clp_req_rsp_list_pci *rrb;
int rc;
@@ -422,7 +432,7 @@ int clp_rescan_pci_devices_simple(void)
if (!rrb)
return -ENOMEM;

- rc = clp_list_pci(rrb, NULL, __clp_update);
+ rc = clp_list_pci(rrb, fid, __clp_update);

clp_free_block(rrb);
return rc;
diff --git a/arch/s390/pci/pci_sysfs.c b/arch/s390/pci/pci_sysfs.c
index a433ba01a317..215f17437a4f 100644
--- a/arch/s390/pci/pci_sysfs.c
+++ b/arch/s390/pci/pci_sysfs.c
@@ -13,6 +13,8 @@
#include <linux/stat.h>
#include <linux/pci.h>

+#include "../../../drivers/pci/pci.h"
+
#include <asm/sclp.h>

#define zpci_attr(name, fmt, member) \
@@ -49,31 +51,50 @@ static DEVICE_ATTR_RO(mio_enabled);
static ssize_t recover_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
+ struct kernfs_node *kn;
struct pci_dev *pdev = to_pci_dev(dev);
struct zpci_dev *zdev = to_zpci(pdev);
- int ret;
-
- if (!device_remove_file_self(dev, attr))
- return count;
-
+ int ret = 0;
+
+ /* Can't use device_remove_self() here as that would lead us to lock
+ * the pci_rescan_remove_lock while holding the device' kernfs lock.
+ * This would create a possible deadlock with disable_slot() which is
+ * not directly protected by the device' kernfs lock but takes it
+ * during the device removal which happens under
+ * pci_rescan_remove_lock.
+ *
+ * This is analogous to sdev_store_delete() in
+ * drivers/scsi/scsi_sysfs.c
+ */
+ kn = sysfs_break_active_protection(&dev->kobj, &attr->attr);
+ WARN_ON_ONCE(!kn);
+ /* device_remove_file() serializes concurrent calls ignoring all but
+ * the first
+ */
+ device_remove_file(dev, attr);
+
+ /* A concurrent call to recover_store() may slip between
+ * sysfs_break_active_protection() and the sysfs file removal.
+ * Once it unblocks from pci_lock_rescan_remove() the original pdev
+ * will already be removed.
+ */
pci_lock_rescan_remove();
- pci_stop_and_remove_bus_device(pdev);
- ret = zpci_disable_device(zdev);
- if (ret)
- goto error;
-
- ret = zpci_enable_device(zdev);
- if (ret)
- goto error;
-
- pci_rescan_bus(zdev->bus);
+ if (pci_dev_is_added(pdev)) {
+ pci_stop_and_remove_bus_device(pdev);
+ ret = zpci_disable_device(zdev);
+ if (ret)
+ goto out;
+
+ ret = zpci_enable_device(zdev);
+ if (ret)
+ goto out;
+ pci_rescan_bus(zdev->bus);
+ }
+out:
pci_unlock_rescan_remove();
-
- return count;
-
-error:
- pci_unlock_rescan_remove();
- return ret;
+ if (kn)
+ sysfs_unbreak_active_protection(kn);
+ return ret ? ret : count;
}
static DEVICE_ATTR_WO(recover);