From bedc61a922f9dbbe3bfb26ec2745f8cd63b57637 Mon Sep 17 00:00:00 2001 From: Andrea Parri Date: Tue, 15 Oct 2019 13:46:44 +0200 Subject: Drivers: hv: vmbus: Introduce table of VMBus protocol versions The technique used to get the next VMBus version seems increasisly clumsy as the number of VMBus versions increases. Performance is not a concern since this is only done once during system boot; it's just that we'll end up with more lines of code than is really needed. As an alternative, introduce a table with the version numbers listed in order (from the most recent to the oldest). vmbus_connect() loops through the versions listed in the table until it gets an accepted connection or gets to the end of the table (invalid version). Suggested-by: Michael Kelley Signed-off-by: Andrea Parri Reviewed-by: Wei Liu Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/connection.c | 50 ++++++++++++++++++------------------------------- drivers/hv/vmbus_drv.c | 3 +-- 2 files changed, 19 insertions(+), 34 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 6e4c015783ff..8dc48f53c1ac 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -40,29 +40,17 @@ EXPORT_SYMBOL_GPL(vmbus_connection); __u32 vmbus_proto_version; EXPORT_SYMBOL_GPL(vmbus_proto_version); -static __u32 vmbus_get_next_version(__u32 current_version) -{ - switch (current_version) { - case (VERSION_WIN7): - return VERSION_WS2008; - - case (VERSION_WIN8): - return VERSION_WIN7; - - case (VERSION_WIN8_1): - return VERSION_WIN8; - - case (VERSION_WIN10): - return VERSION_WIN8_1; - - case (VERSION_WIN10_V5): - return VERSION_WIN10; - - case (VERSION_WS2008): - default: - return VERSION_INVAL; - } -} +/* + * Table of VMBus versions listed from newest to oldest. + */ +static __u32 vmbus_versions[] = { + VERSION_WIN10_V5, + VERSION_WIN10, + VERSION_WIN8_1, + VERSION_WIN8, + VERSION_WIN7, + VERSION_WS2008 +}; int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) { @@ -169,8 +157,8 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) */ int vmbus_connect(void) { - int ret = 0; struct vmbus_channel_msginfo *msginfo = NULL; + int i, ret = 0; __u32 version; /* Initialize the vmbus connection */ @@ -244,21 +232,19 @@ int vmbus_connect(void) * version. */ - version = VERSION_CURRENT; + for (i = 0; ; i++) { + if (i == ARRAY_SIZE(vmbus_versions)) + goto cleanup; + + version = vmbus_versions[i]; - do { ret = vmbus_negotiate_version(msginfo, version); if (ret == -ETIMEDOUT) goto cleanup; if (vmbus_connection.conn_state == CONNECTED) break; - - version = vmbus_get_next_version(version); - } while (version != VERSION_INVAL); - - if (version == VERSION_INVAL) - goto cleanup; + } vmbus_proto_version = version; pr_info("Vmbus version:%d.%d\n", diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 53a60c81e220..0ac874faf720 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -2220,8 +2220,7 @@ static int vmbus_bus_resume(struct device *dev) * We only use the 'vmbus_proto_version', which was in use before * hibernation, to re-negotiate with the host. */ - if (vmbus_proto_version == VERSION_INVAL || - vmbus_proto_version == 0) { + if (!vmbus_proto_version) { pr_err("Invalid proto version = 0x%x\n", vmbus_proto_version); return -EINVAL; } -- cgit v1.2.3 From 2d4f49b3e1e3a24ce16dfeeb2235688c8aba57ef Mon Sep 17 00:00:00 2001 From: Andrea Parri Date: Tue, 15 Oct 2019 13:46:45 +0200 Subject: Drivers: hv: vmbus: Enable VMBus protocol versions 4.1, 5.1 and 5.2 Hyper-V has added VMBus protocol versions 5.1 and 5.2 in recent release versions. Allow Linux guests to negotiate these new protocol versions on versions of Hyper-V that support them. While on this, also allow guests to negotiate the VMBus protocol version 4.1 (which was missing). Signed-off-by: Andrea Parri Reviewed-by: Wei Liu Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/connection.c | 13 ++++++++----- include/linux/hyperv.h | 8 +++++++- 2 files changed, 15 insertions(+), 6 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 8dc48f53c1ac..cadfb34b38d8 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -44,7 +44,10 @@ EXPORT_SYMBOL_GPL(vmbus_proto_version); * Table of VMBus versions listed from newest to oldest. */ static __u32 vmbus_versions[] = { + VERSION_WIN10_V5_2, + VERSION_WIN10_V5_1, VERSION_WIN10_V5, + VERSION_WIN10_V4_1, VERSION_WIN10, VERSION_WIN8_1, VERSION_WIN8, @@ -68,12 +71,12 @@ int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) msg->vmbus_version_requested = version; /* - * VMBus protocol 5.0 (VERSION_WIN10_V5) requires that we must use - * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message, + * VMBus protocol 5.0 (VERSION_WIN10_V5) and higher require that we must + * use VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate Contact Message, * and for subsequent messages, we must use the Message Connection ID * field in the host-returned Version Response Message. And, with - * VERSION_WIN10_V5, we don't use msg->interrupt_page, but we tell - * the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for + * VERSION_WIN10_V5 and higher, we don't use msg->interrupt_page, but we + * tell the host explicitly that we still use VMBUS_MESSAGE_SINT(2) for * compatibility. * * On old hosts, we should always use VMBUS_MESSAGE_CONNECTION_ID (1). @@ -399,7 +402,7 @@ int vmbus_post_msg(void *buffer, size_t buflen, bool can_sleep) case HV_STATUS_INVALID_CONNECTION_ID: /* * See vmbus_negotiate_version(): VMBus protocol 5.0 - * requires that we must use + * and higher require that we must use * VMBUS_MESSAGE_CONNECTION_ID_4 for the Initiate * Contact message, but on old hosts that only * support VMBus protocol 4.0 or lower, here we get diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index c08b62dbd151..f17f2cd22e39 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -182,15 +182,21 @@ static inline u32 hv_get_avail_to_write_percent( * 2 . 4 (Windows 8) * 3 . 0 (Windows 8 R2) * 4 . 0 (Windows 10) + * 4 . 1 (Windows 10 RS3) * 5 . 0 (Newer Windows 10) + * 5 . 1 (Windows 10 RS4) + * 5 . 2 (Windows Server 2019, RS5) */ #define VERSION_WS2008 ((0 << 16) | (13)) #define VERSION_WIN7 ((1 << 16) | (1)) #define VERSION_WIN8 ((2 << 16) | (4)) #define VERSION_WIN8_1 ((3 << 16) | (0)) -#define VERSION_WIN10 ((4 << 16) | (0)) +#define VERSION_WIN10 ((4 << 16) | (0)) +#define VERSION_WIN10_V4_1 ((4 << 16) | (1)) #define VERSION_WIN10_V5 ((5 << 16) | (0)) +#define VERSION_WIN10_V5_1 ((5 << 16) | (1)) +#define VERSION_WIN10_V5_2 ((5 << 16) | (2)) /* Make maximum size of pipe payload of 16K */ #define MAX_PIPE_DATA_PAYLOAD (sizeof(u8) * 16384) -- cgit v1.2.3 From 931cccc967730d43bb6325506baf51c8f83a9a58 Mon Sep 17 00:00:00 2001 From: Andrea Parri Date: Tue, 15 Oct 2019 13:46:46 +0200 Subject: Drivers: hv: vmbus: Add module parameter to cap the VMBus version Currently, Linux guests negotiate the VMBus version with Hyper-V and use the highest available VMBus version they can connect to. This has some drawbacks: by using the highest available version, certain code paths are never executed and can not be tested when the guest runs on the newest host. Add the module parameter "max_version", to upper-bound the VMBus versions guests can negotiate. Suggested-by: Dexuan Cui Signed-off-by: Andrea Parri Reviewed-by: Wei Liu Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/connection.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'drivers/hv') diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index cadfb34b38d8..0475be4356dd 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -55,6 +56,16 @@ static __u32 vmbus_versions[] = { VERSION_WS2008 }; +/* + * Maximal VMBus protocol version guests can negotiate. Useful to cap the + * VMBus version for testing and debugging purpose. + */ +static uint max_version = VERSION_WIN10_V5_2; + +module_param(max_version, uint, S_IRUGO); +MODULE_PARM_DESC(max_version, + "Maximal VMBus protocol version which can be negotiated"); + int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo, u32 version) { int ret = 0; @@ -240,6 +251,8 @@ int vmbus_connect(void) goto cleanup; version = vmbus_versions[i]; + if (version > max_version) + continue; ret = vmbus_negotiate_version(msginfo, version); if (ret == -ETIMEDOUT) -- cgit v1.2.3 From af9ca6f9bb16e446a44393a797d0ae74d356a5c7 Mon Sep 17 00:00:00 2001 From: Branden Bonaby Date: Thu, 3 Oct 2019 17:01:49 -0400 Subject: drivers: hv: vmbus: Introduce latency testing Introduce user specified latency in the packet reception path By exposing the test parameters as part of the debugfs channel attributes. We will control the testing state via these attributes. Signed-off-by: Branden Bonaby Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- Documentation/ABI/testing/debugfs-hyperv | 23 ++++ MAINTAINERS | 1 + drivers/hv/Makefile | 1 + drivers/hv/connection.c | 1 + drivers/hv/hv_debugfs.c | 178 +++++++++++++++++++++++++++++++ drivers/hv/hyperv_vmbus.h | 31 ++++++ drivers/hv/ring_buffer.c | 2 + drivers/hv/vmbus_drv.c | 6 ++ include/linux/hyperv.h | 19 ++++ lib/Kconfig.debug | 7 ++ 10 files changed, 269 insertions(+) create mode 100644 Documentation/ABI/testing/debugfs-hyperv create mode 100644 drivers/hv/hv_debugfs.c (limited to 'drivers/hv') diff --git a/Documentation/ABI/testing/debugfs-hyperv b/Documentation/ABI/testing/debugfs-hyperv new file mode 100644 index 000000000000..9185e1b06bba --- /dev/null +++ b/Documentation/ABI/testing/debugfs-hyperv @@ -0,0 +1,23 @@ +What: /sys/kernel/debug/hyperv//fuzz_test_state +Date: October 2019 +KernelVersion: 5.5 +Contact: Branden Bonaby +Description: Fuzz testing status of a vmbus device, whether its in an ON + state or a OFF state +Users: Debugging tools + +What: /sys/kernel/debug/hyperv//delay/fuzz_test_buffer_interrupt_delay +Date: October 2019 +KernelVersion: 5.5 +Contact: Branden Bonaby +Description: Fuzz testing buffer interrupt delay value between 0 - 1000 + microseconds (inclusive). +Users: Debugging tools + +What: /sys/kernel/debug/hyperv//delay/fuzz_test_message_delay +Date: October 2019 +KernelVersion: 5.5 +Contact: Branden Bonaby +Description: Fuzz testing message delay value between 0 - 1000 microseconds + (inclusive). +Users: Debugging tools diff --git a/MAINTAINERS b/MAINTAINERS index cba1095547fd..e7febfbf44ab 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7578,6 +7578,7 @@ F: include/uapi/linux/hyperv.h F: include/asm-generic/mshyperv.h F: tools/hv/ F: Documentation/ABI/stable/sysfs-bus-vmbus +F: Documentation/ABI/testing/debugfs-hyperv HYPERBUS SUPPORT M: Vignesh Raghavendra diff --git a/drivers/hv/Makefile b/drivers/hv/Makefile index a1eec7177c2d..94daf8240c95 100644 --- a/drivers/hv/Makefile +++ b/drivers/hv/Makefile @@ -9,4 +9,5 @@ CFLAGS_hv_balloon.o = -I$(src) hv_vmbus-y := vmbus_drv.o \ hv.o connection.o channel.o \ channel_mgmt.o ring_buffer.o hv_trace.o +hv_vmbus-$(CONFIG_HYPERV_TESTING) += hv_debugfs.o hv_utils-y := hv_util.o hv_kvp.o hv_snapshot.o hv_fcopy.o hv_utils_transport.o diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index 0475be4356dd..e947c39d4cc7 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -363,6 +363,7 @@ void vmbus_on_event(unsigned long data) trace_vmbus_on_event(channel); + hv_debug_delay_test(channel, INTERRUPT_DELAY); do { void (*callback_fn)(void *); diff --git a/drivers/hv/hv_debugfs.c b/drivers/hv/hv_debugfs.c new file mode 100644 index 000000000000..8a2878573582 --- /dev/null +++ b/drivers/hv/hv_debugfs.c @@ -0,0 +1,178 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Authors: + * Branden Bonaby + */ + +#include +#include +#include +#include + +#include "hyperv_vmbus.h" + +struct dentry *hv_debug_root; + +static int hv_debugfs_delay_get(void *data, u64 *val) +{ + *val = *(u32 *)data; + return 0; +} + +static int hv_debugfs_delay_set(void *data, u64 val) +{ + if (val > 1000) + return -EINVAL; + *(u32 *)data = val; + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(hv_debugfs_delay_fops, hv_debugfs_delay_get, + hv_debugfs_delay_set, "%llu\n"); + +static int hv_debugfs_state_get(void *data, u64 *val) +{ + *val = *(bool *)data; + return 0; +} + +static int hv_debugfs_state_set(void *data, u64 val) +{ + if (val == 1) + *(bool *)data = true; + else if (val == 0) + *(bool *)data = false; + else + return -EINVAL; + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(hv_debugfs_state_fops, hv_debugfs_state_get, + hv_debugfs_state_set, "%llu\n"); + +/* Setup delay files to store test values */ +static int hv_debug_delay_files(struct hv_device *dev, struct dentry *root) +{ + struct vmbus_channel *channel = dev->channel; + char *buffer = "fuzz_test_buffer_interrupt_delay"; + char *message = "fuzz_test_message_delay"; + int *buffer_val = &channel->fuzz_testing_interrupt_delay; + int *message_val = &channel->fuzz_testing_message_delay; + struct dentry *buffer_file, *message_file; + + buffer_file = debugfs_create_file(buffer, 0644, root, + buffer_val, + &hv_debugfs_delay_fops); + if (IS_ERR(buffer_file)) { + pr_debug("debugfs_hyperv: file %s not created\n", buffer); + return PTR_ERR(buffer_file); + } + + message_file = debugfs_create_file(message, 0644, root, + message_val, + &hv_debugfs_delay_fops); + if (IS_ERR(message_file)) { + pr_debug("debugfs_hyperv: file %s not created\n", message); + return PTR_ERR(message_file); + } + + return 0; +} + +/* Setup test state value for vmbus device */ +static int hv_debug_set_test_state(struct hv_device *dev, struct dentry *root) +{ + struct vmbus_channel *channel = dev->channel; + bool *state = &channel->fuzz_testing_state; + char *status = "fuzz_test_state"; + struct dentry *test_state; + + test_state = debugfs_create_file(status, 0644, root, + state, + &hv_debugfs_state_fops); + if (IS_ERR(test_state)) { + pr_debug("debugfs_hyperv: file %s not created\n", status); + return PTR_ERR(test_state); + } + + return 0; +} + +/* Bind hv device to a dentry for debugfs */ +static void hv_debug_set_dir_dentry(struct hv_device *dev, struct dentry *root) +{ + if (hv_debug_root) + dev->debug_dir = root; +} + +/* Create all test dentry's and names for fuzz testing */ +int hv_debug_add_dev_dir(struct hv_device *dev) +{ + const char *device = dev_name(&dev->device); + char *delay_name = "delay"; + struct dentry *delay, *dev_root; + int ret; + + if (!IS_ERR(hv_debug_root)) { + dev_root = debugfs_create_dir(device, hv_debug_root); + if (IS_ERR(dev_root)) { + pr_debug("debugfs_hyperv: hyperv/%s/ not created\n", + device); + return PTR_ERR(dev_root); + } + hv_debug_set_test_state(dev, dev_root); + hv_debug_set_dir_dentry(dev, dev_root); + delay = debugfs_create_dir(delay_name, dev_root); + + if (IS_ERR(delay)) { + pr_debug("debugfs_hyperv: hyperv/%s/%s/ not created\n", + device, delay_name); + return PTR_ERR(delay); + } + ret = hv_debug_delay_files(dev, delay); + + return ret; + } + pr_debug("debugfs_hyperv: hyperv/ not in root debugfs path\n"); + return PTR_ERR(hv_debug_root); +} + +/* Remove dentry associated with released hv device */ +void hv_debug_rm_dev_dir(struct hv_device *dev) +{ + if (!IS_ERR(hv_debug_root)) + debugfs_remove_recursive(dev->debug_dir); +} + +/* Remove all dentrys associated with vmbus testing */ +void hv_debug_rm_all_dir(void) +{ + debugfs_remove_recursive(hv_debug_root); +} + +/* Delay buffer/message reads on a vmbus channel */ +void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type) +{ + struct vmbus_channel *test_channel = channel->primary_channel ? + channel->primary_channel : + channel; + bool state = test_channel->fuzz_testing_state; + + if (state) { + if (delay_type == 0) + udelay(test_channel->fuzz_testing_interrupt_delay); + else + udelay(test_channel->fuzz_testing_message_delay); + } +} + +/* Initialize top dentry for vmbus testing */ +int hv_debug_init(void) +{ + hv_debug_root = debugfs_create_dir("hyperv", NULL); + if (IS_ERR(hv_debug_root)) { + pr_debug("debugfs_hyperv: hyperv/ not created\n"); + return PTR_ERR(hv_debug_root); + } + return 0; +} diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h index af9379a3bf89..20edcfd3b96c 100644 --- a/drivers/hv/hyperv_vmbus.h +++ b/drivers/hv/hyperv_vmbus.h @@ -385,4 +385,35 @@ enum hvutil_device_state { HVUTIL_DEVICE_DYING, /* driver unload is in progress */ }; +enum delay { + INTERRUPT_DELAY = 0, + MESSAGE_DELAY = 1, +}; + +#ifdef CONFIG_HYPERV_TESTING + +int hv_debug_add_dev_dir(struct hv_device *dev); +void hv_debug_rm_dev_dir(struct hv_device *dev); +void hv_debug_rm_all_dir(void); +int hv_debug_init(void); +void hv_debug_delay_test(struct vmbus_channel *channel, enum delay delay_type); + +#else /* CONFIG_HYPERV_TESTING */ + +static inline void hv_debug_rm_dev_dir(struct hv_device *dev) {}; +static inline void hv_debug_rm_all_dir(void) {}; +static inline void hv_debug_delay_test(struct vmbus_channel *channel, + enum delay delay_type) {}; +static inline int hv_debug_init(void) +{ + return -1; +} + +static inline int hv_debug_add_dev_dir(struct hv_device *dev) +{ + return -1; +} + +#endif /* CONFIG_HYPERV_TESTING */ + #endif /* _HYPERV_VMBUS_H */ diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c index 9a03b163cbbd..356e22159e83 100644 --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -396,6 +396,7 @@ struct vmpacket_descriptor *hv_pkt_iter_first(struct vmbus_channel *channel) struct hv_ring_buffer_info *rbi = &channel->inbound; struct vmpacket_descriptor *desc; + hv_debug_delay_test(channel, MESSAGE_DELAY); if (hv_pkt_iter_avail(rbi) < sizeof(struct vmpacket_descriptor)) return NULL; @@ -421,6 +422,7 @@ __hv_pkt_iter_next(struct vmbus_channel *channel, u32 packetlen = desc->len8 << 3; u32 dsize = rbi->ring_datasize; + hv_debug_delay_test(channel, MESSAGE_DELAY); /* bump offset to next potential packet */ rbi->priv_read_index += packetlen + VMBUS_PKT_TRAILER; if (rbi->priv_read_index >= dsize) diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 0ac874faf720..125991820278 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -960,6 +960,8 @@ static void vmbus_device_release(struct device *device) struct hv_device *hv_dev = device_to_hv_device(device); struct vmbus_channel *channel = hv_dev->channel; + hv_debug_rm_dev_dir(hv_dev); + mutex_lock(&vmbus_connection.channel_mutex); hv_process_channel_removal(channel); mutex_unlock(&vmbus_connection.channel_mutex); @@ -1814,6 +1816,7 @@ int vmbus_device_register(struct hv_device *child_device_obj) pr_err("Unable to register primary channeln"); goto err_kset_unregister; } + hv_debug_add_dev_dir(child_device_obj); return 0; @@ -2374,6 +2377,7 @@ static int __init hv_acpi_init(void) ret = -ETIMEDOUT; goto cleanup; } + hv_debug_init(); ret = vmbus_bus_init(); if (ret) @@ -2410,6 +2414,8 @@ static void __exit vmbus_exit(void) tasklet_kill(&hv_cpu->msg_dpc); } + hv_debug_rm_all_dir(); + vmbus_free_channels(); if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h index f17f2cd22e39..26f3aeeae1ca 100644 --- a/include/linux/hyperv.h +++ b/include/linux/hyperv.h @@ -934,6 +934,21 @@ struct vmbus_channel { * full outbound ring buffer. */ u64 out_full_first; + + /* enabling/disabling fuzz testing on the channel (default is false)*/ + bool fuzz_testing_state; + + /* + * Interrupt delay will delay the guest from emptying the ring buffer + * for a specific amount of time. The delay is in microseconds and will + * be between 1 to a maximum of 1000, its default is 0 (no delay). + * The Message delay will delay guest reading on a per message basis + * in microseconds between 1 to 1000 with the default being 0 + * (no delay). + */ + u32 fuzz_testing_interrupt_delay; + u32 fuzz_testing_message_delay; + }; static inline bool is_hvsock_channel(const struct vmbus_channel *c) @@ -1182,6 +1197,10 @@ struct hv_device { struct vmbus_channel *channel; struct kset *channels_kset; + + /* place holder to keep track of the dir for hv device in debugfs */ + struct dentry *debug_dir; + }; diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 93d97f9b0157..55eebbc0b0fb 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -2127,4 +2127,11 @@ config IO_STRICT_DEVMEM source "arch/$(SRCARCH)/Kconfig.debug" +config HYPERV_TESTING + bool "Microsoft Hyper-V driver testing" + default n + depends on HYPERV && DEBUG_FS + help + Select this option to enable Hyper-V vmbus testing. + endmenu # Kernel hacking -- cgit v1.2.3 From b14d749ac5abdf311321172ae11e6ad1be4293e9 Mon Sep 17 00:00:00 2001 From: Himadri Pandya Date: Thu, 25 Jul 2019 05:03:14 +0000 Subject: Drivers: hv: Specify receive buffer size using Hyper-V page size The recv_buffer is used to retrieve data from the VMbus ring buffer. VMbus ring buffers are sized based on the guest page size which Hyper-V assumes to be 4KB. But it may be different on some architectures. So use the Hyper-V page size to allocate the recv_buffer and set the maximum size to receive. Signed-off-by: Himadri Pandya Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/hv_fcopy.c | 3 ++- drivers/hv/hv_kvp.c | 3 ++- drivers/hv/hv_snapshot.c | 3 ++- drivers/hv/hv_util.c | 8 ++++---- 4 files changed, 10 insertions(+), 7 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/hv_fcopy.c b/drivers/hv/hv_fcopy.c index 7e30ae0635cc..08fa4a5de644 100644 --- a/drivers/hv/hv_fcopy.c +++ b/drivers/hv/hv_fcopy.c @@ -13,6 +13,7 @@ #include #include #include +#include #include "hyperv_vmbus.h" #include "hv_utils_transport.h" @@ -234,7 +235,7 @@ void hv_fcopy_onchannelcallback(void *context) if (fcopy_transaction.state > HVUTIL_READY) return; - vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen, + vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen, &requestid); if (recvlen <= 0) return; diff --git a/drivers/hv/hv_kvp.c b/drivers/hv/hv_kvp.c index 5054d1105236..ae7c028dc5a8 100644 --- a/drivers/hv/hv_kvp.c +++ b/drivers/hv/hv_kvp.c @@ -27,6 +27,7 @@ #include #include #include +#include #include "hyperv_vmbus.h" #include "hv_utils_transport.h" @@ -661,7 +662,7 @@ void hv_kvp_onchannelcallback(void *context) if (kvp_transaction.state > HVUTIL_READY) return; - vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen, + vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 4, &recvlen, &requestid); if (recvlen > 0) { diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c index 20ba95b75a94..03b6454268b3 100644 --- a/drivers/hv/hv_snapshot.c +++ b/drivers/hv/hv_snapshot.c @@ -12,6 +12,7 @@ #include #include #include +#include #include "hyperv_vmbus.h" #include "hv_utils_transport.h" @@ -297,7 +298,7 @@ void hv_vss_onchannelcallback(void *context) if (vss_transaction.state > HVUTIL_READY) return; - vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen, + vmbus_recvpacket(channel, recv_buffer, HV_HYP_PAGE_SIZE * 2, &recvlen, &requestid); if (recvlen > 0) { diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c index e32681ee7b9f..c2c08f26bd5f 100644 --- a/drivers/hv/hv_util.c +++ b/drivers/hv/hv_util.c @@ -136,7 +136,7 @@ static void shutdown_onchannelcallback(void *context) struct icmsg_hdr *icmsghdrp; vmbus_recvpacket(channel, shut_txf_buf, - PAGE_SIZE, &recvlen, &requestid); + HV_HYP_PAGE_SIZE, &recvlen, &requestid); if (recvlen > 0) { icmsghdrp = (struct icmsg_hdr *)&shut_txf_buf[ @@ -284,7 +284,7 @@ static void timesync_onchannelcallback(void *context) u8 *time_txf_buf = util_timesynch.recv_buffer; vmbus_recvpacket(channel, time_txf_buf, - PAGE_SIZE, &recvlen, &requestid); + HV_HYP_PAGE_SIZE, &recvlen, &requestid); if (recvlen > 0) { icmsghdrp = (struct icmsg_hdr *)&time_txf_buf[ @@ -346,7 +346,7 @@ static void heartbeat_onchannelcallback(void *context) while (1) { vmbus_recvpacket(channel, hbeat_txf_buf, - PAGE_SIZE, &recvlen, &requestid); + HV_HYP_PAGE_SIZE, &recvlen, &requestid); if (!recvlen) break; @@ -390,7 +390,7 @@ static int util_probe(struct hv_device *dev, (struct hv_util_service *)dev_id->driver_data; int ret; - srv->recv_buffer = kmalloc(PAGE_SIZE * 4, GFP_KERNEL); + srv->recv_buffer = kmalloc(HV_HYP_PAGE_SIZE * 4, GFP_KERNEL); if (!srv->recv_buffer) return -ENOMEM; srv->channel = dev->channel; -- cgit v1.2.3 From 0541a225945d5e0d650353f51614812aa820c6be Mon Sep 17 00:00:00 2001 From: Himadri Pandya Date: Thu, 25 Jul 2019 05:03:15 +0000 Subject: Drivers: hv: util: Specify ring buffer size using Hyper-V page size VMbus ring buffers are sized based on the 4K page size used by Hyper-V. The Linux guest page size may not be 4K on all architectures so use the Hyper-V page size to specify the ring buffer size. Signed-off-by: Himadri Pandya Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/hv_util.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/hv_util.c b/drivers/hv/hv_util.c index c2c08f26bd5f..766bd8457346 100644 --- a/drivers/hv/hv_util.c +++ b/drivers/hv/hv_util.c @@ -413,8 +413,9 @@ static int util_probe(struct hv_device *dev, hv_set_drvdata(dev, srv); - ret = vmbus_open(dev->channel, 4 * PAGE_SIZE, 4 * PAGE_SIZE, NULL, 0, - srv->util_cb, dev->channel); + ret = vmbus_open(dev->channel, 4 * HV_HYP_PAGE_SIZE, + 4 * HV_HYP_PAGE_SIZE, NULL, 0, srv->util_cb, + dev->channel); if (ret) goto error; -- cgit v1.2.3 From 53edce00ceb7443b6f4615b5c8ad71671723d8f5 Mon Sep 17 00:00:00 2001 From: Himadri Pandya Date: Tue, 30 Jul 2019 09:49:44 +0000 Subject: Drivers: hv: vmbus: Remove dependencies on guest page size Hyper-V assumes page size to be 4K. This might not be the case for ARM64 architecture. Hence use hyper-v page size and page allocation function to avoid conflicts between different host and guest page size on ARM64. Signed-off-by: Himadri Pandya Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/connection.c | 14 +++++++------- drivers/hv/vmbus_drv.c | 6 +++--- 2 files changed, 10 insertions(+), 10 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c index e947c39d4cc7..74e77de89b4f 100644 --- a/drivers/hv/connection.c +++ b/drivers/hv/connection.c @@ -208,7 +208,7 @@ int vmbus_connect(void) * abstraction stuff */ vmbus_connection.int_page = - (void *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, 0); + (void *)hv_alloc_hyperv_zeroed_page(); if (vmbus_connection.int_page == NULL) { ret = -ENOMEM; goto cleanup; @@ -217,14 +217,14 @@ int vmbus_connect(void) vmbus_connection.recv_int_page = vmbus_connection.int_page; vmbus_connection.send_int_page = (void *)((unsigned long)vmbus_connection.int_page + - (PAGE_SIZE >> 1)); + (HV_HYP_PAGE_SIZE >> 1)); /* * Setup the monitor notification facility. The 1st page for * parent->child and the 2nd page for child->parent */ - vmbus_connection.monitor_pages[0] = (void *)__get_free_pages((GFP_KERNEL|__GFP_ZERO), 0); - vmbus_connection.monitor_pages[1] = (void *)__get_free_pages((GFP_KERNEL|__GFP_ZERO), 0); + vmbus_connection.monitor_pages[0] = (void *)hv_alloc_hyperv_zeroed_page(); + vmbus_connection.monitor_pages[1] = (void *)hv_alloc_hyperv_zeroed_page(); if ((vmbus_connection.monitor_pages[0] == NULL) || (vmbus_connection.monitor_pages[1] == NULL)) { ret = -ENOMEM; @@ -297,12 +297,12 @@ void vmbus_disconnect(void) destroy_workqueue(vmbus_connection.work_queue); if (vmbus_connection.int_page) { - free_pages((unsigned long)vmbus_connection.int_page, 0); + hv_free_hyperv_page((unsigned long)vmbus_connection.int_page); vmbus_connection.int_page = NULL; } - free_pages((unsigned long)vmbus_connection.monitor_pages[0], 0); - free_pages((unsigned long)vmbus_connection.monitor_pages[1], 0); + hv_free_hyperv_page((unsigned long)vmbus_connection.monitor_pages[0]); + hv_free_hyperv_page((unsigned long)vmbus_connection.monitor_pages[1]); vmbus_connection.monitor_pages[0] = NULL; vmbus_connection.monitor_pages[1] = NULL; } diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 125991820278..5d2304b4b9c8 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1275,7 +1275,7 @@ static void hv_kmsg_dump(struct kmsg_dumper *dumper, * Write dump contents to the page. No need to synchronize; panic should * be single-threaded. */ - kmsg_dump_get_buffer(dumper, true, hv_panic_page, PAGE_SIZE, + kmsg_dump_get_buffer(dumper, true, hv_panic_page, HV_HYP_PAGE_SIZE, &bytes_written); if (bytes_written) hyperv_report_panic_msg(panic_pa, bytes_written); @@ -1379,7 +1379,7 @@ static int vmbus_bus_init(void) */ hv_get_crash_ctl(hyperv_crash_ctl); if (hyperv_crash_ctl & HV_CRASH_CTL_CRASH_NOTIFY_MSG) { - hv_panic_page = (void *)get_zeroed_page(GFP_KERNEL); + hv_panic_page = (void *)hv_alloc_hyperv_zeroed_page(); if (hv_panic_page) { ret = kmsg_dump_register(&hv_kmsg_dumper); if (ret) @@ -1408,7 +1408,7 @@ err_alloc: hv_remove_vmbus_irq(); bus_unregister(&hv_bus); - free_page((unsigned long)hv_panic_page); + hv_free_hyperv_page((unsigned long)hv_panic_page); unregister_sysctl_table(hv_ctl_table_hdr); hv_ctl_table_hdr = NULL; return ret; -- cgit v1.2.3 From 2af5e7b7b230f3c6dcc9d72bb7eeda6e1df1f5fa Mon Sep 17 00:00:00 2001 From: Himadri Pandya Date: Sat, 17 Aug 2019 04:08:50 +0000 Subject: Drivers: hv: balloon: Remove dependencies on guest page size Hyper-V assumes page size to be 4K. This might not be the case for ARM64 architecture. Hence use hyper-v specific page size and page shift definitions to avoid conflicts between different host and guest page sizes on ARM64. Also, remove some old and incorrect comments and redefine ballooning granularities to handle larger page sizes correctly. Signed-off-by: Himadri Pandya Reviewed-by: Michael Kelley Signed-off-by: Sasha Levin --- drivers/hv/hv_balloon.c | 25 ++++++++++++------------- 1 file changed, 12 insertions(+), 13 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 34bd73526afd..935904830d42 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -23,6 +23,7 @@ #include #include +#include #define CREATE_TRACE_POINTS #include "hv_trace_balloon.h" @@ -341,8 +342,6 @@ struct dm_unballoon_response { * * mem_range: Memory range to hot add. * - * On Linux we currently don't support this since we cannot hot add - * arbitrary granularity of memory. */ struct dm_hot_add { @@ -477,7 +476,7 @@ module_param(pressure_report_delay, uint, (S_IRUGO | S_IWUSR)); MODULE_PARM_DESC(pressure_report_delay, "Delay in secs in reporting pressure"); static atomic_t trans_id = ATOMIC_INIT(0); -static int dm_ring_size = (5 * PAGE_SIZE); +static int dm_ring_size = 20 * 1024; /* * Driver specific state. @@ -493,10 +492,10 @@ enum hv_dm_state { }; -static __u8 recv_buffer[PAGE_SIZE]; -static __u8 balloon_up_send_buffer[PAGE_SIZE]; -#define PAGES_IN_2M 512 -#define HA_CHUNK (32 * 1024) +static __u8 recv_buffer[HV_HYP_PAGE_SIZE]; +static __u8 balloon_up_send_buffer[HV_HYP_PAGE_SIZE]; +#define PAGES_IN_2M (2 * 1024 * 1024 / PAGE_SIZE) +#define HA_CHUNK (128 * 1024 * 1024 / PAGE_SIZE) struct hv_dynmem_device { struct hv_device *dev; @@ -1076,7 +1075,7 @@ static void process_info(struct hv_dynmem_device *dm, struct dm_info_msg *msg) __u64 *max_page_count = (__u64 *)&info_hdr[1]; pr_info("Max. dynamic memory size: %llu MB\n", - (*max_page_count) >> (20 - PAGE_SHIFT)); + (*max_page_count) >> (20 - HV_HYP_PAGE_SHIFT)); } break; @@ -1218,7 +1217,7 @@ static unsigned int alloc_balloon_pages(struct hv_dynmem_device *dm, for (i = 0; (i * alloc_unit) < num_pages; i++) { if (bl_resp->hdr.size + sizeof(union dm_mem_page_range) > - PAGE_SIZE) + HV_HYP_PAGE_SIZE) return i * alloc_unit; /* @@ -1274,9 +1273,9 @@ static void balloon_up(struct work_struct *dummy) /* * We will attempt 2M allocations. However, if we fail to - * allocate 2M chunks, we will go back to 4k allocations. + * allocate 2M chunks, we will go back to PAGE_SIZE allocations. */ - alloc_unit = 512; + alloc_unit = PAGES_IN_2M; avail_pages = si_mem_available(); floor = compute_balloon_floor(); @@ -1292,7 +1291,7 @@ static void balloon_up(struct work_struct *dummy) } while (!done) { - memset(balloon_up_send_buffer, 0, PAGE_SIZE); + memset(balloon_up_send_buffer, 0, HV_HYP_PAGE_SIZE); bl_resp = (struct dm_balloon_response *)balloon_up_send_buffer; bl_resp->hdr.type = DM_BALLOON_RESPONSE; bl_resp->hdr.size = sizeof(struct dm_balloon_response); @@ -1491,7 +1490,7 @@ static void balloon_onchannelcallback(void *context) memset(recv_buffer, 0, sizeof(recv_buffer)); vmbus_recvpacket(dev->channel, recv_buffer, - PAGE_SIZE, &recvlen, &requestid); + HV_HYP_PAGE_SIZE, &recvlen, &requestid); if (recvlen > 0) { dm_msg = (struct dm_message *)recv_buffer; -- cgit v1.2.3 From 25bd2b2f1f05347a4cd633138d0e4c2fd5788359 Mon Sep 17 00:00:00 2001 From: Dexuan Cui Date: Tue, 19 Nov 2019 23:16:05 -0800 Subject: hv_balloon: Add the support of hibernation When hibernation is enabled, we must ignore the balloon up/down and hot-add requests from the host, if any. Signed-off-by: Dexuan Cui Acked-by: David Hildenbrand Signed-off-by: Sasha Levin --- drivers/hv/hv_balloon.c | 87 +++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 85 insertions(+), 2 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 935904830d42..7f4cf4fc805e 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -25,6 +25,8 @@ #include #include +#include + #define CREATE_TRACE_POINTS #include "hv_trace_balloon.h" @@ -456,6 +458,7 @@ struct hot_add_wrk { struct work_struct wrk; }; +static bool allow_hibernation; static bool hot_add = true; static bool do_hot_add; /* @@ -1052,8 +1055,12 @@ static void hot_add_req(struct work_struct *dummy) else resp.result = 0; - if (!do_hot_add || (resp.page_count == 0)) - pr_err("Memory hot add failed\n"); + if (!do_hot_add || resp.page_count == 0) { + if (!allow_hibernation) + pr_err("Memory hot add failed\n"); + else + pr_info("Ignore hot-add request!\n"); + } dm->state = DM_INITIALIZED; resp.hdr.trans_id = atomic_inc_return(&trans_id); @@ -1508,6 +1515,11 @@ static void balloon_onchannelcallback(void *context) break; case DM_BALLOON_REQUEST: + if (allow_hibernation) { + pr_info("Ignore balloon-up request!\n"); + break; + } + if (dm->state == DM_BALLOON_UP) pr_warn("Currently ballooning\n"); bal_msg = (struct dm_balloon *)recv_buffer; @@ -1517,6 +1529,11 @@ static void balloon_onchannelcallback(void *context) break; case DM_UNBALLOON_REQUEST: + if (allow_hibernation) { + pr_info("Ignore balloon-down request!\n"); + break; + } + dm->state = DM_BALLOON_DOWN; balloon_down(dm, (struct dm_unballoon_request *)recv_buffer); @@ -1622,6 +1639,11 @@ static int balloon_connect_vsp(struct hv_device *dev) cap_msg.hdr.size = sizeof(struct dm_capabilities); cap_msg.hdr.trans_id = atomic_inc_return(&trans_id); + /* + * When hibernation (i.e. virtual ACPI S4 state) is enabled, the host + * currently still requires the bits to be set, so we have to add code + * to fail the host's hot-add and balloon up/down requests, if any. + */ cap_msg.caps.cap_bits.balloon = 1; cap_msg.caps.cap_bits.hot_add = 1; @@ -1671,6 +1693,10 @@ static int balloon_probe(struct hv_device *dev, { int ret; + allow_hibernation = hv_is_hibernation_supported(); + if (allow_hibernation) + hot_add = false; + #ifdef CONFIG_MEMORY_HOTPLUG do_hot_add = hot_add; #else @@ -1710,6 +1736,8 @@ static int balloon_probe(struct hv_device *dev, return 0; probe_error: + dm_device.state = DM_INIT_ERROR; + dm_device.thread = NULL; vmbus_close(dev->channel); #ifdef CONFIG_MEMORY_HOTPLUG unregister_memory_notifier(&hv_memory_nb); @@ -1751,6 +1779,59 @@ static int balloon_remove(struct hv_device *dev) return 0; } +static int balloon_suspend(struct hv_device *hv_dev) +{ + struct hv_dynmem_device *dm = hv_get_drvdata(hv_dev); + + tasklet_disable(&hv_dev->channel->callback_event); + + cancel_work_sync(&dm->balloon_wrk.wrk); + cancel_work_sync(&dm->ha_wrk.wrk); + + if (dm->thread) { + kthread_stop(dm->thread); + dm->thread = NULL; + vmbus_close(hv_dev->channel); + } + + tasklet_enable(&hv_dev->channel->callback_event); + + return 0; + +} + +static int balloon_resume(struct hv_device *dev) +{ + int ret; + + dm_device.state = DM_INITIALIZING; + + ret = balloon_connect_vsp(dev); + + if (ret != 0) + goto out; + + dm_device.thread = + kthread_run(dm_thread_func, &dm_device, "hv_balloon"); + if (IS_ERR(dm_device.thread)) { + ret = PTR_ERR(dm_device.thread); + dm_device.thread = NULL; + goto close_channel; + } + + dm_device.state = DM_INITIALIZED; + return 0; +close_channel: + vmbus_close(dev->channel); +out: + dm_device.state = DM_INIT_ERROR; +#ifdef CONFIG_MEMORY_HOTPLUG + unregister_memory_notifier(&hv_memory_nb); + restore_online_page_callback(&hv_online_page); +#endif + return ret; +} + static const struct hv_vmbus_device_id id_table[] = { /* Dynamic Memory Class ID */ /* 525074DC-8985-46e2-8057-A307DC18A502 */ @@ -1765,6 +1846,8 @@ static struct hv_driver balloon_drv = { .id_table = id_table, .probe = balloon_probe, .remove = balloon_remove, + .suspend = balloon_suspend, + .resume = balloon_resume, .driver = { .probe_type = PROBE_PREFER_ASYNCHRONOUS, }, -- cgit v1.2.3 From 8aea7f82153d6f292add3eb4bd7ba8edcae5c7f7 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Fri, 1 Nov 2019 13:00:04 -0700 Subject: drivers/hv: Replace binary semaphore with mutex At a slight footprint cost (24 vs 32 bytes), mutexes are more optimal than semaphores; it's also a nicer interface for mutual exclusion, which is why they are encouraged over binary semaphores, when possible. Replace the hyperv_mmio_lock, its semantics implies traditional lock ownership; that is, the lock owner is the same for both lock/unlock operations. Therefore it is safe to convert. Signed-off-by: Davidlohr Bueso Signed-off-by: Sasha Levin --- drivers/hv/vmbus_drv.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'drivers/hv') diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 5d2304b4b9c8..845d2a9423ea 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -79,7 +79,7 @@ static struct notifier_block hyperv_panic_block = { static const char *fb_mmio_name = "fb_range"; static struct resource *fb_mmio; static struct resource *hyperv_mmio; -static DEFINE_SEMAPHORE(hyperv_mmio_lock); +static DEFINE_MUTEX(hyperv_mmio_lock); static int vmbus_exists(void) { @@ -2018,7 +2018,7 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj, int retval; retval = -ENXIO; - down(&hyperv_mmio_lock); + mutex_lock(&hyperv_mmio_lock); /* * If overlaps with frame buffers are allowed, then first attempt to @@ -2065,7 +2065,7 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj, } exit: - up(&hyperv_mmio_lock); + mutex_unlock(&hyperv_mmio_lock); return retval; } EXPORT_SYMBOL_GPL(vmbus_allocate_mmio); @@ -2082,7 +2082,7 @@ void vmbus_free_mmio(resource_size_t start, resource_size_t size) { struct resource *iter; - down(&hyperv_mmio_lock); + mutex_lock(&hyperv_mmio_lock); for (iter = hyperv_mmio; iter; iter = iter->sibling) { if ((iter->start >= start + size) || (iter->end <= start)) continue; @@ -2090,7 +2090,7 @@ void vmbus_free_mmio(resource_size_t start, resource_size_t size) __release_region(iter, start, size); } release_mem_region(start, size); - up(&hyperv_mmio_lock); + mutex_unlock(&hyperv_mmio_lock); } EXPORT_SYMBOL_GPL(vmbus_free_mmio); -- cgit v1.2.3 From 7a1323b5dfe44a9013a2cc56ef2973034a00bf88 Mon Sep 17 00:00:00 2001 From: Michael Kelley Date: Thu, 14 Nov 2019 06:32:01 +0000 Subject: Drivers: hv: vmbus: Fix crash handler reset of Hyper-V synic The crash handler calls hv_synic_cleanup() to shutdown the Hyper-V synthetic interrupt controller. But if the CPU that calls hv_synic_cleanup() has a VMbus channel interrupt assigned to it (which is likely the case in smaller VM sizes), hv_synic_cleanup() returns an error and the synthetic interrupt controller isn't shutdown. While the lack of being shutdown hasn't caused a known problem, it still should be fixed for highest reliability. So directly call hv_synic_disable_regs() instead of hv_synic_cleanup(), which ensures that the synic is always shutdown. Signed-off-by: Michael Kelley Reviewed-by: Vitaly Kuznetsov Reviewed-by: Dexuan Cui Signed-off-by: Sasha Levin --- drivers/hv/vmbus_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/hv') diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index 845d2a9423ea..f3d0bddc80a7 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -2310,7 +2310,7 @@ static void hv_crash_handler(struct pt_regs *regs) vmbus_connection.conn_state = DISCONNECTED; cpu = smp_processor_id(); hv_stimer_cleanup(cpu); - hv_synic_cleanup(cpu); + hv_synic_disable_regs(cpu); hyperv_cleanup(); }; -- cgit v1.2.3