From 1b948134c00673c0dc902a72474df3261c4bbbcd Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Mon, 12 Nov 2018 13:05:22 +0200 Subject: intel_th: Update ABI documentation Commit a753bfcfdb1f3 ("intel_th: Make the switch allocate its subdevices") changed the behavior so that the output port devices are created only for the ports reported by the hardware and their initial state is "unassigned" until a corresponding output port driver is loaded. Reflect this fact in the ABI documentation. Signed-off-by: Alexander Shishkin Reported-by: Ricardo Neri --- Documentation/ABI/testing/sysfs-bus-intel_th-output-devices | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-bus-intel_th-output-devices b/Documentation/ABI/testing/sysfs-bus-intel_th-output-devices index 4d48a9451866..d1f667104944 100644 --- a/Documentation/ABI/testing/sysfs-bus-intel_th-output-devices +++ b/Documentation/ABI/testing/sysfs-bus-intel_th-output-devices @@ -3,11 +3,13 @@ Date: June 2015 KernelVersion: 4.3 Contact: Alexander Shishkin Description: (RW) Writes of 1 or 0 enable or disable trace output to this - output device. Reads return current status. + output device. Reads return current status. Requires that the + correstponding output port driver be loaded. What: /sys/bus/intel_th/devices/-msc/port Date: June 2015 KernelVersion: 4.3 Contact: Alexander Shishkin Description: (RO) Port number, corresponding to this output device on the - switch (GTH). + switch (GTH) or "unassigned" if the corresponding output + port driver is not loaded. -- cgit v1.2.3 From 8d86f6b4306f4be38b39d420456edf61a7b7119e Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 12 Feb 2019 15:43:02 -0600 Subject: intel_th: Mark expected switch fall-throughs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In preparation to enabling -Wimplicit-fallthrough, mark switch cases where we are expecting to fall through. This patch fixes the following warnings: drivers/hwtracing/intel_th/sth.c: In function ‘sth_stm_packet’: drivers/hwtracing/intel_th/sth.c:86:7: warning: this statement may fall through [-Wimplicit-fallthrough=] reg += 4; ~~~~^~~~ drivers/hwtracing/intel_th/sth.c:87:2: note: here case STP_PACKET_XSYNC: ^~~~ drivers/hwtracing/intel_th/sth.c:88:7: warning: this statement may fall through [-Wimplicit-fallthrough=] reg += 8; ~~~~^~~~ drivers/hwtracing/intel_th/sth.c:89:2: note: here case STP_PACKET_TRIG: ^~~~ Warning level 3 was used: -Wimplicit-fallthrough=3 This patch is part of the ongoing efforts to enable -Wimplicit-fallthrough. Signed-off-by: Gustavo A. R. Silva Signed-off-by: Alexander Shishkin --- drivers/hwtracing/intel_th/sth.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/hwtracing/intel_th/sth.c b/drivers/hwtracing/intel_th/sth.c index 4b7ae47789d2..3a1f4e650378 100644 --- a/drivers/hwtracing/intel_th/sth.c +++ b/drivers/hwtracing/intel_th/sth.c @@ -84,8 +84,12 @@ static ssize_t notrace sth_stm_packet(struct stm_data *stm_data, /* Global packets (GERR, XSYNC, TRIG) are sent with register writes */ case STP_PACKET_GERR: reg += 4; + /* fall through */ + case STP_PACKET_XSYNC: reg += 8; + /* fall through */ + case STP_PACKET_TRIG: if (flags & STP_PACKET_TIMESTAMPED) reg += 4; -- cgit v1.2.3 From ba828cc9dcc8ffefd0d17165be9b132bd5232063 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Mon, 12 Nov 2018 13:30:24 +0200 Subject: intel_th: Only create useful device nodes Right now, the driver will create a device node for each output port, with the intent to provide read access to that port's data. However, only the memory ports are readable this way (msc0, msc1). Other output ports don't need device nodes, so remove them. Signed-off-by: Alexander Shishkin --- drivers/hwtracing/intel_th/core.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c index fc6b7f8b62fb..7c1acc2f801c 100644 --- a/drivers/hwtracing/intel_th/core.c +++ b/drivers/hwtracing/intel_th/core.c @@ -422,6 +422,7 @@ static const struct intel_th_subdevice { unsigned nres; unsigned type; unsigned otype; + bool mknode; unsigned scrpd; int id; } intel_th_subdevices[] = { @@ -456,6 +457,7 @@ static const struct intel_th_subdevice { .name = "msc", .id = 0, .type = INTEL_TH_OUTPUT, + .mknode = true, .otype = GTH_MSU, .scrpd = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC0_IS_ENABLED, }, @@ -476,6 +478,7 @@ static const struct intel_th_subdevice { .name = "msc", .id = 1, .type = INTEL_TH_OUTPUT, + .mknode = true, .otype = GTH_MSU, .scrpd = SCRPD_MEM_IS_PRIM_DEST | SCRPD_MSC1_IS_ENABLED, }, @@ -635,7 +638,8 @@ intel_th_subdevice_alloc(struct intel_th *th, } if (subdev->type == INTEL_TH_OUTPUT) { - thdev->dev.devt = MKDEV(th->major, th->num_thdevs); + if (subdev->mknode) + thdev->dev.devt = MKDEV(th->major, th->num_thdevs); thdev->output.type = subdev->otype; thdev->output.port = -1; thdev->output.scratchpad = subdev->scrpd; -- cgit v1.2.3 From 1d2ef028bf9a9272c658782d9c75f60658770ba4 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 4 May 2018 22:19:25 +0300 Subject: intel_th: pti: Use sysfs_match_string() helper Use sysfs_match_string() helper instead of open coded variant. Signed-off-by: Andy Shevchenko Signed-off-by: Alexander Shishkin --- drivers/hwtracing/intel_th/pti.c | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/drivers/hwtracing/intel_th/pti.c b/drivers/hwtracing/intel_th/pti.c index 56694339cb06..0da6b787f553 100644 --- a/drivers/hwtracing/intel_th/pti.c +++ b/drivers/hwtracing/intel_th/pti.c @@ -272,19 +272,17 @@ static ssize_t lpp_dest_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { struct pti_device *pti = dev_get_drvdata(dev); - ssize_t ret = -EINVAL; int i; - for (i = 0; i < ARRAY_SIZE(lpp_dest_str); i++) - if (sysfs_streq(buf, lpp_dest_str[i])) - break; + i = sysfs_match_string(lpp_dest_str, buf); + if (i < 0) + return i; - if (i < ARRAY_SIZE(lpp_dest_str) && pti->lpp_dest_mask & BIT(i)) { - pti->lpp_dest = i; - ret = size; - } + if (!(pti->lpp_dest_mask & BIT(i))) + return -EINVAL; - return ret; + pti->lpp_dest = i; + return size; } static DEVICE_ATTR_RW(lpp_dest); -- cgit v1.2.3 From 9ed3f22223c33347ed963e7c7019cf2956dd4e37 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Thu, 24 Jan 2019 15:11:53 +0200 Subject: intel_th: Don't reference unassigned outputs When an output port driver is removed, also remove references to it from any masters. Failing to do this causes a NULL ptr dereference when configuring another output port: > BUG: unable to handle kernel NULL pointer dereference at 000000000000000d > RIP: 0010:master_attr_store+0x9d/0x160 [intel_th_gth] > Call Trace: > dev_attr_store+0x1b/0x30 > sysfs_kf_write+0x3c/0x50 > kernfs_fop_write+0x125/0x1a0 > __vfs_write+0x3a/0x190 > ? __vfs_write+0x5/0x190 > ? _cond_resched+0x1a/0x50 > ? rcu_all_qs+0x5/0xb0 > ? __vfs_write+0x5/0x190 > vfs_write+0xb8/0x1b0 > ksys_write+0x55/0xc0 > __x64_sys_write+0x1a/0x20 > do_syscall_64+0x5a/0x140 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: Alexander Shishkin Fixes: b27a6a3f97b9 ("intel_th: Add Global Trace Hub driver") CC: stable@vger.kernel.org # v4.4+ Reported-by: Ammy Yi --- drivers/hwtracing/intel_th/gth.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/hwtracing/intel_th/gth.c b/drivers/hwtracing/intel_th/gth.c index 8426b7970c14..cc287cf6eb29 100644 --- a/drivers/hwtracing/intel_th/gth.c +++ b/drivers/hwtracing/intel_th/gth.c @@ -607,6 +607,7 @@ static void intel_th_gth_unassign(struct intel_th_device *thdev, { struct gth_device *gth = dev_get_drvdata(&thdev->dev); int port = othdev->output.port; + int master; if (thdev->host_mode) return; @@ -615,6 +616,9 @@ static void intel_th_gth_unassign(struct intel_th_device *thdev, othdev->output.port = -1; othdev->output.active = false; gth->output[port].output = NULL; + for (master = 0; master < TH_CONFIGURABLE_MASTERS; master++) + if (gth->master[master] == port) + gth->master[master] = -1; spin_unlock(>h->gth_lock); } -- cgit v1.2.3 From a1d75dad3a2c689e70a1c4e0214cca9de741d0aa Mon Sep 17 00:00:00 2001 From: Zhi Jin Date: Thu, 6 Sep 2018 15:22:10 +0800 Subject: stm class: Fix an endless loop in channel allocation There is a bug in the channel allocation logic that leads to an endless loop when looking for a contiguous range of channels in a range with a mixture of free and occupied channels. For example, opening three consequtive channels, closing the first two and requesting 4 channels in a row will trigger this soft lockup. The bug is that the search loop forgets to skip over the range once it detects that one channel in that range is occupied. Restore the original intent to the logic by fixing the omission. Signed-off-by: Zhi Jin Signed-off-by: Alexander Shishkin Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices") CC: stable@vger.kernel.org # v4.4+ --- drivers/hwtracing/stm/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index 93ce3aa740a9..c80b064224f6 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -244,6 +244,9 @@ static int find_free_channels(unsigned long *bitmap, unsigned int start, ; if (i == width) return pos; + + /* step over [pos..pos+i) to continue search */ + pos += i; } return -1; -- cgit v1.2.3 From bf7cbaae0831252b416f375ca9b1027ecd4642dd Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Thu, 21 Feb 2019 14:19:17 +0200 Subject: stm class: Prevent division by zero Using STP_POLICY_ID_SET ioctl command with dummy_stm device, or any STM device that supplies zero mmio channel size, will trigger a division by zero bug in the kernel. Prevent this by disallowing channel widths other than 1 for such devices. Signed-off-by: Alexander Shishkin Fixes: 7bd1d4093c2f ("stm class: Introduce an abstraction for System Trace Module devices") CC: stable@vger.kernel.org # v4.4+ --- drivers/hwtracing/stm/core.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c index c80b064224f6..c7ba8acfd4d5 100644 --- a/drivers/hwtracing/stm/core.c +++ b/drivers/hwtracing/stm/core.c @@ -735,7 +735,7 @@ static int stm_char_policy_set_ioctl(struct stm_file *stmf, void __user *arg) struct stm_device *stm = stmf->stm; struct stp_policy_id *id; char *ids[] = { NULL, NULL }; - int ret = -EINVAL; + int ret = -EINVAL, wlimit = 1; u32 size; if (stmf->output.nr_chans) @@ -763,8 +763,10 @@ static int stm_char_policy_set_ioctl(struct stm_file *stmf, void __user *arg) if (id->__reserved_0 || id->__reserved_1) goto err_free; - if (id->width < 1 || - id->width > PAGE_SIZE / stm->data->sw_mmiosz) + if (stm->data->sw_mmiosz) + wlimit = PAGE_SIZE / stm->data->sw_mmiosz; + + if (id->width < 1 || id->width > wlimit) goto err_free; ids[0] = id->id; -- cgit v1.2.3