In sgx_init(), if misc_register() fails or misc_register() succeeds but
neither sgx_drv_init() nor sgx_vepc_init() succeeds, then ksgxd will be
prematurely stopped. This may leave some unsanitized pages, which does
not matter, because SGX will be disabled for the whole power cycle.
This triggers WARN_ON() because sgx_dirty_page_list ends up being
non-empty, and dumps the call stack:
[ 0.268103] sgx: EPC section 0x40200000-0x45f7ffff
[ 0.268591] ------------[ cut here ]------------
[ 0.268592] WARNING: CPU: 6 PID: 83 at
arch/x86/kernel/cpu/sgx/main.c:401 ksgxd+0x1b7/0x1d0
[ 0.268598] Modules linked in:
[ 0.268600] CPU: 6 PID: 83 Comm: ksgxd Not tainted 6.0.0-rc2 #382
[ 0.268603] Hardware name: Dell Inc. XPS 13 9370/0RMYH9, BIOS 1.21.0
07/06/2022
[ 0.268604] RIP: 0010:ksgxd+0x1b7/0x1d0
[ 0.268607] Code: ff e9 f2 fe ff ff 48 89 df e8 75 07 0e 00 84 c0 0f
84 c3 fe ff ff 31 ff e8 e6 07 0e 00 84 c0 0f 85 94 fe ff ff e9 af fe ff
ff <0f> 0b e9 7f fe ff ff e8 dd 9c 95 00 66 66 2e 0f 1f 84 00 00 00 00
[ 0.268608] RSP: 0000:ffffb6c7404f3ed8 EFLAGS: 00010287
[ 0.268610] RAX: ffffb6c740431a10 RBX: ffff8dcd8117b400 RCX:
0000000000000000
[ 0.268612] RDX: 0000000080000000 RSI: ffffb6c7404319d0 RDI:
00000000ffffffff
[ 0.268613] RBP: ffff8dcd820a4d80 R08: ffff8dcd820a4180 R09:
ffff8dcd820a4180
[ 0.268614] R10: 0000000000000000 R11: 0000000000000006 R12:
ffffb6c74006bce0
[ 0.268615] R13: ffff8dcd80e63880 R14: ffffffffa8a60f10 R15:
0000000000000000
[ 0.268616] FS: 0000000000000000(0000) GS:ffff8dcf25580000(0000)
knlGS:0000000000000000
[ 0.268617] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 0.268619] CR2: 0000000000000000 CR3: 0000000213410001 CR4:
00000000003706e0
[ 0.268620] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[ 0.268621] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[ 0.268622] Call Trace:
[ 0.268624] <TASK>
[ 0.268627] ? _raw_spin_lock_irqsave+0x24/0x60
[ 0.268632] ? _raw_spin_unlock_irqrestore+0x23/0x40
[ 0.268634] ? __kthread_parkme+0x36/0x90
[ 0.268637] kthread+0xe5/0x110
[ 0.268639] ? kthread_complete_and_exit+0x20/0x20
[ 0.268642] ret_from_fork+0x1f/0x30
[ 0.268647] </TASK>
[ 0.268648] ---[ end trace 0000000000000000 ]---
Ultimately this can crash the kernel, if the following is set:
/proc/sys/kernel/panic_on_warn
In premature stop, print nothing, as the number is by practical means a
random number. Otherwise, it is an indicator of a bug in the driver, and
therefore print the number of unsanitized pages with pr_err().
Link: https://lore.kernel.org/linux-sgx/20220825051827.246698-1-jarkko@kernel.org…
Fixes: 51ab30eb2ad4 ("x86/sgx: Replace section->init_laundry_list with sgx_dirty_page_list")
Cc: stable(a)vger.kernel.org # v5.13+
Reported-by: Paul Menzel <pmenzel(a)molgen.mpg.de>
Signed-off-by: Jarkko Sakkinen <jarkko(a)kernel.org>
---
v6:
- Address Reinette's feedback:
https://lore.kernel.org/linux-sgx/Yw6%2FiTzSdSw%2FY%2FVO@kernel.org/
v5:
- Add the klog dump and sysctl option to the commit message.
v4:
- Explain expectations for dirty_page_list in the function header, instead
of an inline comment.
- Improve commit message to explain the conditions better.
- Return the number of pages left dirty to ksgxd() and print warning after
the 2nd call, if there are any.
v3:
- Remove WARN_ON().
- Tuned comments and the commit message a bit.
v2:
- Replaced WARN_ON() with optional pr_info() inside
__sgx_sanitize_pages().
- Rewrote the commit message.
- Added the fixes tag.
---
arch/x86/kernel/cpu/sgx/main.c | 42 ++++++++++++++++++++++++++++------
1 file changed, 35 insertions(+), 7 deletions(-)
diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index 515e2a5f25bb..bcd6b64961bd 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -49,17 +49,20 @@ static LIST_HEAD(sgx_dirty_page_list);
* Reset post-kexec EPC pages to the uninitialized state. The pages are removed
* from the input list, and made available for the page allocator. SECS pages
* prepending their children in the input list are left intact.
+ *
+ * Contents of the @dirty_page_list must be thread-local, i.e.
+ * not shared by multiple threads.
*/
-static void __sgx_sanitize_pages(struct list_head *dirty_page_list)
+static long __sgx_sanitize_pages(struct list_head *dirty_page_list)
{
struct sgx_epc_page *page;
+ long left_dirty = 0;
LIST_HEAD(dirty);
int ret;
- /* dirty_page_list is thread-local, no need for a lock: */
while (!list_empty(dirty_page_list)) {
if (kthread_should_stop())
- return;
+ return -ECANCELED;
page = list_first_entry(dirty_page_list, struct sgx_epc_page, list);
@@ -92,12 +95,14 @@ static void __sgx_sanitize_pages(struct list_head *dirty_page_list)
} else {
/* The page is not yet clean - move to the dirty list. */
list_move_tail(&page->list, &dirty);
+ left_dirty++;
}
cond_resched();
}
list_splice(&dirty, dirty_page_list);
+ return left_dirty;
}
static bool sgx_reclaimer_age(struct sgx_epc_page *epc_page)
@@ -388,17 +393,40 @@ void sgx_reclaim_direct(void)
static int ksgxd(void *p)
{
+ long ret;
+
set_freezable();
/*
* Sanitize pages in order to recover from kexec(). The 2nd pass is
* required for SECS pages, whose child pages blocked EREMOVE.
*/
- __sgx_sanitize_pages(&sgx_dirty_page_list);
- __sgx_sanitize_pages(&sgx_dirty_page_list);
+ ret = __sgx_sanitize_pages(&sgx_dirty_page_list);
+ if (ret == -ECANCELED)
+ /* kthread stopped */
+ return 0;
- /* sanity check: */
- WARN_ON(!list_empty(&sgx_dirty_page_list));
+ ret = __sgx_sanitize_pages(&sgx_dirty_page_list);
+ switch (ret) {
+ case 0:
+ /* success, no unsanitized pages */
+ break;
+
+ case -ECANCELED:
+ /* kthread stopped */
+ return 0;
+
+ default:
+ /*
+ * Never expected to happen in a working driver. If it happens
+ * the bug is expected to be in the sanitization process, but
+ * successfully sanitized pages are still valid and driver can
+ * be used and most importantly debugged without issues. To put
+ * short, the global state of kernel is not corrupted so no
+ * reason to do any more complicated rollback.
+ */
+ pr_err("%ld unsanitized pages\n", ret);
+ }
while (!kthread_should_stop()) {
if (try_to_freeze())
--
2.37.2
The advertisement of the persistent grants feature (writing
'feature-persistent' to xenbus) should mean not the decision for using
the feature but only the availability of the feature. However, commit
aac8a70db24b ("xen-blkback: add a parameter for disabling of persistent
grants") made a field of blkback, which was a place for saving only the
negotiation result, to be used for yet another purpose: caching of the
'feature_persistent' parameter value. As a result, the advertisement,
which should follow only the parameter value, becomes inconsistent.
This commit fixes the misuse of the semantic by making blkback saves the
parameter value in a separate place and advertises the support based on
only the saved value.
Fixes: aac8a70db24b ("xen-blkback: add a parameter for disabling of persistent grants")
Cc: <stable(a)vger.kernel.org> # 5.10.x
Suggested-by: Juergen Gross <jgross(a)suse.com>
Signed-off-by: SeongJae Park <sj(a)kernel.org>
---
drivers/block/xen-blkback/common.h | 3 +++
drivers/block/xen-blkback/xenbus.c | 6 ++++--
2 files changed, 7 insertions(+), 2 deletions(-)
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index bda5c815e441..a28473470e66 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -226,6 +226,9 @@ struct xen_vbd {
sector_t size;
unsigned int flush_support:1;
unsigned int discard_secure:1;
+ /* Connect-time cached feature_persistent parameter value */
+ unsigned int feature_gnt_persistent_parm:1;
+ /* Persistent grants feature negotiation result */
unsigned int feature_gnt_persistent:1;
unsigned int overflow_max_grants:1;
};
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index ee7ad2fb432d..c0227dfa4688 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -907,7 +907,7 @@ static void connect(struct backend_info *be)
xen_blkbk_barrier(xbt, be, be->blkif->vbd.flush_support);
err = xenbus_printf(xbt, dev->nodename, "feature-persistent", "%u",
- be->blkif->vbd.feature_gnt_persistent);
+ be->blkif->vbd.feature_gnt_persistent_parm);
if (err) {
xenbus_dev_fatal(dev, err, "writing %s/feature-persistent",
dev->nodename);
@@ -1085,7 +1085,9 @@ static int connect_ring(struct backend_info *be)
return -ENOSYS;
}
- blkif->vbd.feature_gnt_persistent = feature_persistent &&
+ blkif->vbd.feature_gnt_persistent_parm = feature_persistent;
+ blkif->vbd.feature_gnt_persistent =
+ blkif->vbd.feature_gnt_persistent_parm &&
xenbus_read_unsigned(dev->otherend, "feature-persistent", 0);
blkif->vbd.overflow_max_grants = 0;
--
2.25.1
We need to inform PCODE of a desired ring frequencies so PCODE update
the memory frequencies to us. rps->min_freq and rps->max_freq are the
frequencies used in that request. However they were unset when SLPC was
enabled and PCODE never updated the memory freq.
v2 (as Suggested by Ashutosh): if SLPC is in use, let's pick the right
frequencies from the get_ia_constants instead of the fake init of
rps' min and max.
Fixes: 7ba79a671568 ("drm/i915/guc/slpc: Gate Host RPS when SLPC is enabled")
Cc: <stable(a)vger.kernel.org> # v5.15+
Cc: Ashutosh Dixit <ashutosh.dixit(a)intel.com>
Tested-by: Sushma Venkatesh Reddy <sushma.venkatesh.reddy(a)intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi(a)intel.com>
---
drivers/gpu/drm/i915/gt/intel_llc.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/i915/gt/intel_llc.c b/drivers/gpu/drm/i915/gt/intel_llc.c
index 14fe65812e42..766f9526da99 100644
--- a/drivers/gpu/drm/i915/gt/intel_llc.c
+++ b/drivers/gpu/drm/i915/gt/intel_llc.c
@@ -49,6 +49,7 @@ static unsigned int cpu_max_MHz(void)
static bool get_ia_constants(struct intel_llc *llc,
struct ia_constants *consts)
{
+ struct intel_guc_slpc *slpc = &llc_to_gt(llc)->uc.guc.slpc;
struct drm_i915_private *i915 = llc_to_gt(llc)->i915;
struct intel_rps *rps = &llc_to_gt(llc)->rps;
@@ -65,8 +66,13 @@ static bool get_ia_constants(struct intel_llc *llc,
/* convert DDR frequency from units of 266.6MHz to bandwidth */
consts->min_ring_freq = mult_frac(consts->min_ring_freq, 8, 3);
- consts->min_gpu_freq = rps->min_freq;
- consts->max_gpu_freq = rps->max_freq;
+ if (intel_uc_uses_guc_slpc(&llc_to_gt(llc)->uc)) {
+ consts->min_gpu_freq = slpc->min_freq;
+ consts->max_gpu_freq = slpc->rp0_freq;
+ } else {
+ consts->min_gpu_freq = rps->min_freq;
+ consts->max_gpu_freq = rps->max_freq;
+ }
if (GRAPHICS_VER(i915) >= 9) {
/* Convert GT frequency to 50 HZ units */
consts->min_gpu_freq /= GEN9_FREQ_SCALER;
--
2.37.1
Both __device_attach_driver() and __driver_attach() check the return
code of the bus_type.match() function to see if the device needs to be
added to the deferred probe list. After adding the device to the list,
the logic attempts to bind the device to the driver anyway, as if the
device had matched with the driver, which is not correct.
If __device_attach_driver() detects that the device in question is not
ready to match with a driver on the bus, then it doesn't make sense for
the device to attempt to bind with the current driver or continue
attempting to match with any of the other drivers on the bus. So, update
the logic in __device_attach_driver() to reflect this.
If __driver_attach() detects that a driver tried to match with a device
that is not ready to match yet, then the driver should not attempt to bind
with the device. However, the driver can still attempt to match and bind
with other devices on the bus, as drivers can be bound to multiple
devices. So, update the logic in __driver_attach() to reflect this.
Cc: stable(a)vger.kernel.org
Cc: Saravana Kannan <saravanak(a)google.com>
Fixes: 656b8035b0ee ("ARM: 8524/1: driver cohandle -EPROBE_DEFER from bus_type.match()")
Reported-by: Guenter Roeck <linux(a)roeck-us.net>
Signed-off-by: Isaac J. Manjarres <isaacmanjarres(a)google.com>
Tested-by: Guenter Roeck <linux(a)roeck-us.net>
Reviewed-by: Saravana Kannan <saravanak(a)google.com>
---
drivers/base/dd.c | 10 ++++++++++
1 file changed, 10 insertions(+)
v1 -> v2:
- Fixed the logic in __driver_attach() to allow a driver to continue
attempting to match and bind with devices in case of any error, not
just probe deferral.
v2 -> v3:
- Restored the patch back to v1.
- Added Guenter's Tested-by tag.
- Added Saravana's Reviewed-by tag.
- Cc'd stable(a)vger.kernel.org
Greg,
This is the final version of this patch. Can you please pick this up?
Thanks,
Isaac
diff --git a/drivers/base/dd.c b/drivers/base/dd.c
index 70f79fc71539..90b31fb141a5 100644
--- a/drivers/base/dd.c
+++ b/drivers/base/dd.c
@@ -881,6 +881,11 @@ static int __device_attach_driver(struct device_driver *drv, void *_data)
dev_dbg(dev, "Device match requests probe deferral\n");
dev->can_match = true;
driver_deferred_probe_add(dev);
+ /*
+ * Device can't match with a driver right now, so don't attempt
+ * to match or bind with other drivers on the bus.
+ */
+ return ret;
} else if (ret < 0) {
dev_dbg(dev, "Bus failed to match device: %d\n", ret);
return ret;
@@ -1120,6 +1125,11 @@ static int __driver_attach(struct device *dev, void *data)
dev_dbg(dev, "Device match requests probe deferral\n");
dev->can_match = true;
driver_deferred_probe_add(dev);
+ /*
+ * Driver could not match with device, but may match with
+ * another device on the bus.
+ */
+ return 0;
} else if (ret < 0) {
dev_dbg(dev, "Bus failed to match device: %d\n", ret);
return ret;
--
2.37.1.595.g718a3a8f04-goog
Like crashk_res, Calling crash_exclude_mem_range function with
crashk_low_res area would need extra crash_mem range too.
Add one more extra cmem slot in case of crashk_low_res is used.
Signed-off-by: Levi Yun <ppbuk5246(a)gmail.com>
Fixes: 944a45abfabc ("arm64: kdump: Reimplement crashkernel=X")
Cc: <stable(a)vger.kernel.org> # 5.19.x
Acked-by: Baoquan He <bhe(a)redhat.com>
Reviewed-by: Catalin Marinas <catalin.marinas(a)arm.com>
---
arch/arm64/kernel/machine_kexec_file.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 889951291cc0..a11a6e14ba89 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -47,7 +47,7 @@ static int prepare_elf_headers(void **addr, unsigned long *sz)
u64 i;
phys_addr_t start, end;
- nr_ranges = 1; /* for exclusion of crashkernel region */
+ nr_ranges = 2; /* for exclusion of crashkernel region */
for_each_mem_range(i, &start, &end)
nr_ranges++;
--
2.35.1