linux-stable.git/Documentation, branch linux-5.6.y Linux kernel stable tree lib/lzo: fix ambiguous encoding bug in lzo-rle 2020-06-17T14:41:58+00:00 Dave Rodgman dave.rodgman@arm.com 2020-06-12T00:34:54+00:00 ac3cc80984a565eec97932f8658bb3c5c7431a05 commit b5265c813ce4efbfa2e46fd27cdf9a7f44a35d2e upstream. In some rare cases, for input data over 32 KB, lzo-rle could encode two different inputs to the same compressed representation, so that decompression is then ambiguous (i.e. data may be corrupted - although zram is not affected because it operates over 4 KB pages). This modifies the compressor without changing the decompressor or the bitstream format, such that: - there is no change to how data produced by the old compressor is decompressed - an old decompressor will correctly decode data from the updated compressor - performance and compression ratio are not affected - we avoid introducing a new bitstream format In testing over 12.8M real-world files totalling 903 GB, three files were affected by this bug. I also constructed 37M semi-random 64 KB files totalling 2.27 TB, and saw no affected files. Finally I tested over files constructed to contain each of the ~1024 possible bad input sequences; for all of these cases, updated lzo-rle worked correctly. There is no significant impact to performance or compression ratio. Signed-off-by: Dave Rodgman <dave.rodgman@arm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Dave Rodgman <dave.rodgman@arm.com> Cc: Willy Tarreau <w@1wt.eu> Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Markus F.X.J. Oberhumer <markus@oberhumer.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Chao Yu <yuchao0@huawei.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200507100203.29785-1-dave.rodgman@arm.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b5265c813ce4efbfa2e46fd27cdf9a7f44a35d2e upstream.

In some rare cases, for input data over 32 KB, lzo-rle could encode two
different inputs to the same compressed representation, so that
decompression is then ambiguous (i.e.  data may be corrupted - although
zram is not affected because it operates over 4 KB pages).

This modifies the compressor without changing the decompressor or the
bitstream format, such that:

 - there is no change to how data produced by the old compressor is
   decompressed

 - an old decompressor will correctly decode data from the updated
   compressor

 - performance and compression ratio are not affected

 - we avoid introducing a new bitstream format

In testing over 12.8M real-world files totalling 903 GB, three files
were affected by this bug.  I also constructed 37M semi-random 64 KB
files totalling 2.27 TB, and saw no affected files.  Finally I tested
over files constructed to contain each of the ~1024 possible bad input
sequences; for all of these cases, updated lzo-rle worked correctly.

There is no significant impact to performance or compression ratio.

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Rodgman <dave.rodgman@arm.com>
Cc: Willy Tarreau <w@1wt.eu>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: Markus F.X.J. Oberhumer <markus@oberhumer.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Chao Yu <yuchao0@huawei.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200507100203.29785-1-dave.rodgman@arm.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/speculation: Add Ivy Bridge to affected list 2020-06-10T18:22:53+00:00 Josh Poimboeuf jpoimboe@redhat.com 2020-04-27T18:46:13+00:00 1e6cd20e44d4578c39a6bffbd84638bfb4c4d73b commit 3798cc4d106e91382bfe016caa2edada27c2bb3f upstream Make the docs match the code. Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3798cc4d106e91382bfe016caa2edada27c2bb3f upstream

Make the docs match the code.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/speculation: Add SRBDS vulnerability and mitigation documentation 2020-06-10T18:22:52+00:00 Mark Gross mgross@linux.intel.com 2020-04-16T16:21:51+00:00 897d1639c38691742c36d4c3f3c099396b18d314 commit 7222a1b5b87417f22265c92deea76a6aecd0fb0f upstream Add documentation for the SRBDS vulnerability and its mitigation. [ bp: Massage. jpoimboe: sysfs table strings. ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7222a1b5b87417f22265c92deea76a6aecd0fb0f upstream

Add documentation for the SRBDS vulnerability and its mitigation.

 [ bp: Massage.
   jpoimboe: sysfs table strings. ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
x86/speculation: Add Special Register Buffer Data Sampling (SRBDS) mitigation 2020-06-10T18:22:52+00:00 Mark Gross mgross@linux.intel.com 2020-04-16T15:54:04+00:00 49491339c97686dc697aff1b1ddcb426d62f9eff commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream SRBDS is an MDS-like speculative side channel that can leak bits from the random number generator (RNG) across cores and threads. New microcode serializes the processor access during the execution of RDRAND and RDSEED. This ensures that the shared buffer is overwritten before it is released for reuse. While it is present on all affected CPU models, the microcode mitigation is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the cases where TSX is not supported or has been disabled with TSX_CTRL. The mitigation is activated by default on affected processors and it increases latency for RDRAND and RDSEED instructions. Among other effects this will reduce throughput from /dev/urandom. * Enable administrator to configure the mitigation off when desired using either mitigations=off or srbds=off. * Export vulnerability status via sysfs * Rename file-scoped macros to apply for non-whitelist table initializations. [ bp: Massage, - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g, - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in, - flip check in cpu_set_bug_bits() to save an indentation level, - reflow comments. jpoimboe: s/Mitigated/Mitigation/ in user-visible strings tglx: Dropped the fused off magic for now ] Signed-off-by: Mark Gross <mgross@linux.intel.com> Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Tony Luck <tony.luck@intel.com> Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com> Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com> Tested-by: Neelima Krishnan <neelima.krishnan@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 7e5b3c267d256822407a22fdce6afdf9cd13f9fb upstream

SRBDS is an MDS-like speculative side channel that can leak bits from the
random number generator (RNG) across cores and threads. New microcode
serializes the processor access during the execution of RDRAND and
RDSEED. This ensures that the shared buffer is overwritten before it is
released for reuse.

While it is present on all affected CPU models, the microcode mitigation
is not needed on models that enumerate ARCH_CAPABILITIES[MDS_NO] in the
cases where TSX is not supported or has been disabled with TSX_CTRL.

The mitigation is activated by default on affected processors and it
increases latency for RDRAND and RDSEED instructions. Among other
effects this will reduce throughput from /dev/urandom.

* Enable administrator to configure the mitigation off when desired using
  either mitigations=off or srbds=off.

* Export vulnerability status via sysfs

* Rename file-scoped macros to apply for non-whitelist table initializations.

 [ bp: Massage,
   - s/VULNBL_INTEL_STEPPING/VULNBL_INTEL_STEPPINGS/g,
   - do not read arch cap MSR a second time in tsx_fused_off() - just pass it in,
   - flip check in cpu_set_bug_bits() to save an indentation level,
   - reflow comments.
   jpoimboe: s/Mitigated/Mitigation/ in user-visible strings
   tglx: Dropped the fused off magic for now
 ]

Signed-off-by: Mark Gross <mgross@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Reviewed-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Neelima Krishnan <neelima.krishnan@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
bpf: Restrict bpf_trace_printk()'s %s usage and add %pks, %pus specifier 2020-05-20T06:22:38+00:00 Daniel Borkmann daniel@iogearbox.net 2020-05-15T10:11:18+00:00 0a51e9ae051436660800b9aa703e626c3e3966d5 commit b2a5212fb634561bb734c6356904e37f6665b955 upstream. Usage of plain %s conversion specifier in bpf_trace_printk() suffers from the very same issue as bpf_probe_read{,str}() helpers, that is, it is broken on archs with overlapping address ranges. While the helpers have been addressed through work in 6ae08ae3dea2 ("bpf: Add probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers"), we need an option for bpf_trace_printk() as well to fix it. Similarly as with the helpers, force users to make an explicit choice by adding %pks and %pus specifier to bpf_trace_printk() which will then pick the corresponding strncpy_from_unsafe*() variant to perform the access under KERNEL_DS or USER_DS. The %pk* (kernel specifier) and %pu* (user specifier) can later also be extended for other objects aside strings that are probed and printed under tracing, and reused out of other facilities like bpf_seq_printf() or BTF based type printing. Existing behavior of %s for current users is still kept working for archs where it is not broken and therefore gated through CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE. For archs not having this property we fall-back to pick probing under KERNEL_DS as a sensible default. Fixes: 8d3b7dce8622 ("bpf: add support for %s specifier to bpf_trace_printk()") Reported-by: Linus Torvalds <torvalds@linux-foundation.org> Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Brendan Gregg <brendan.d.gregg@gmail.com> Link: https://lore.kernel.org/bpf/20200515101118.6508-4-daniel@iogearbox.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b2a5212fb634561bb734c6356904e37f6665b955 upstream.

Usage of plain %s conversion specifier in bpf_trace_printk() suffers from the
very same issue as bpf_probe_read{,str}() helpers, that is, it is broken on
archs with overlapping address ranges.

While the helpers have been addressed through work in 6ae08ae3dea2 ("bpf: Add
probe_read_{user, kernel} and probe_read_{user, kernel}_str helpers"), we need
an option for bpf_trace_printk() as well to fix it.

Similarly as with the helpers, force users to make an explicit choice by adding
%pks and %pus specifier to bpf_trace_printk() which will then pick the corresponding
strncpy_from_unsafe*() variant to perform the access under KERNEL_DS or USER_DS.
The %pk* (kernel specifier) and %pu* (user specifier) can later also be extended
for other objects aside strings that are probed and printed under tracing, and
reused out of other facilities like bpf_seq_printf() or BTF based type printing.

Existing behavior of %s for current users is still kept working for archs where it
is not broken and therefore gated through CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE.
For archs not having this property we fall-back to pick probing under KERNEL_DS as
a sensible default.

Fixes: 8d3b7dce8622 ("bpf: add support for %s specifier to bpf_trace_printk()")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Brendan Gregg <brendan.d.gregg@gmail.com>
Link: https://lore.kernel.org/bpf/20200515101118.6508-4-daniel@iogearbox.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dt-bindings: dma: fsl-edma: fix ls1028a-edma compatible 2020-05-20T06:22:36+00:00 Michael Walle michael@walle.cc 2020-03-06T20:54:02+00:00 6b9c587512691388ac0e4ddf6d01fe158f508a14 commit d94a05f87327143f94f67dd256932163ac2bcd65 upstream. The bootloader will fix up the IOMMU entries only on nodes with the compatible "fsl,vf610-edma". Thus make this compatible string mandatory for the ls1028a-edma. While at it, fix the "fsl,fsl," typo. Signed-off-by: Michael Walle <michael@walle.cc> Fixes: d8c1bdb5288d ("dt-bindings: dma: fsl-edma: add new fsl,fsl,ls1028a-edma") Signed-off-by: Shawn Guo <shawnguo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit d94a05f87327143f94f67dd256932163ac2bcd65 upstream.

The bootloader will fix up the IOMMU entries only on nodes with the
compatible "fsl,vf610-edma". Thus make this compatible string mandatory
for the ls1028a-edma.

While at it, fix the "fsl,fsl," typo.

Signed-off-by: Michael Walle <michael@walle.cc>
Fixes: d8c1bdb5288d ("dt-bindings: dma: fsl-edma: add new fsl,fsl,ls1028a-edma")
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB: hub: Revert commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") 2020-04-29T14:34:45+00:00 Alan Stern stern@rowland.harvard.edu 2020-04-22T20:13:08+00:00 f8092b0e021762ab73656d6ec87a6c9e90aff4f4 commit 3155f4f40811c5d7e3c686215051acf504e05565 upstream. Commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") changed the way the hub driver enumerates high-speed devices. Instead of using the "new" enumeration scheme first and switching to the "old" scheme if that doesn't work, we start with the "old" scheme. In theory this is better because the "old" scheme is slightly faster -- it involves resetting the device only once instead of twice. However, for a long time Windows used only the "new" scheme. Zeng Tao said that Windows 8 and later use the "old" scheme for high-speed devices, but apparently there are some devices that don't like it. William Bader reports that the Ricoh webcam built into his Sony Vaio laptop not only doesn't enumerate under the "old" scheme, it gets hung up so badly that it won't then enumerate under the "new" scheme! Only a cold reset will fix it. Therefore we will revert the commit and go back to trying the "new" scheme first for high-speed devices. Reported-and-tested-by: William Bader <williambader@hotmail.com> Ref: https://bugzilla.kernel.org/show_bug.cgi?id=207219 Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Fixes: bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices") CC: Zeng Tao <prime.zeng@hisilicon.com> CC: <stable@vger.kernel.org> Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221611230.11262-100000@iolanthe.rowland.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 3155f4f40811c5d7e3c686215051acf504e05565 upstream.

Commit bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for
high speed devices") changed the way the hub driver enumerates
high-speed devices.  Instead of using the "new" enumeration scheme
first and switching to the "old" scheme if that doesn't work, we start
with the "old" scheme.  In theory this is better because the "old"
scheme is slightly faster -- it involves resetting the device only
once instead of twice.

However, for a long time Windows used only the "new" scheme.  Zeng Tao
said that Windows 8 and later use the "old" scheme for high-speed
devices, but apparently there are some devices that don't like it.
William Bader reports that the Ricoh webcam built into his Sony Vaio
laptop not only doesn't enumerate under the "old" scheme, it gets hung
up so badly that it won't then enumerate under the "new" scheme!  Only
a cold reset will fix it.

Therefore we will revert the commit and go back to trying the "new"
scheme first for high-speed devices.

Reported-and-tested-by: William Bader <williambader@hotmail.com>
Ref: https://bugzilla.kernel.org/show_bug.cgi?id=207219
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: bd0e6c9614b9 ("usb: hub: try old enumeration scheme first for high speed devices")
CC: Zeng Tao <prime.zeng@hisilicon.com>
CC: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/Pine.LNX.4.44L0.2004221611230.11262-100000@iolanthe.rowland.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
docs: Fix path to MTD command line partition parser 2020-04-23T08:38:25+00:00 Jonathan Neuschäfer j.neuschaefer@gmx.net 2020-02-18T15:02:19+00:00 93814a21a812b9ce10296a5e2be16a568d857c4d commit fb2511247dc4061fd122d0195838278a4a0b7b59 upstream. cmdlinepart.c has been moved to drivers/mtd/parsers/. Fixes: a3f12a35c91d ("mtd: parsers: Move CMDLINE parser") Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit fb2511247dc4061fd122d0195838278a4a0b7b59 upstream.

cmdlinepart.c has been moved to drivers/mtd/parsers/.

Fixes: a3f12a35c91d ("mtd: parsers: Move CMDLINE parser")
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dt-bindings: thermal: tsens: Fix nvmem-cell-names schema 2020-04-23T08:38:11+00:00 Rob Herring robh@kernel.org 2020-03-24T18:05:12+00:00 a40308ba866b6aba339b051fdbe0600481f8db37 [ Upstream commit b9589def9f9af93d9d4c5969c9a6c166f070e36e ] There's a typo 'nvmem-cells-names' in the schema which means the correct 'nvmem-cell-names' in the examples are not checked. The possible values are wrong too both in that the 2nd entry is not specified correctly and the values are just wrong based on the dts files in the kernel. Fixes: a877e768f655 ("dt-bindings: thermal: tsens: Convert over to a yaml schema") Cc: Andy Gross <agross@kernel.org> Cc: Bjorn Andersson <bjorn.andersson@linaro.org> Cc: Amit Kucheria <amit.kucheria@linaro.org> Cc: Zhang Rui <rui.zhang@intel.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-arm-msm@vger.kernel.org Cc: linux-pm@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Rob Herring <robh@kernel.org> Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit b9589def9f9af93d9d4c5969c9a6c166f070e36e ]

There's a typo 'nvmem-cells-names' in the schema which means the correct
'nvmem-cell-names' in the examples are not checked. The possible values
are wrong too both in that the 2nd entry is not specified correctly and the
values are just wrong based on the dts files in the kernel.

Fixes: a877e768f655 ("dt-bindings: thermal: tsens: Convert over to a yaml schema")
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Amit Kucheria <amit.kucheria@linaro.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arm64: tegra: Fix Tegra194 PCIe compatible string 2020-04-23T08:38:03+00:00 Jon Hunter jonathanh@nvidia.com 2020-02-14T13:53:53+00:00 595f6853a92cb47d7da46c7a583693c9c5182cc6 [ Upstream commit f9f711efd441ad0d22874be49986d92121862335 ] If the kernel configuration option CONFIG_PCIE_DW_PLAT_HOST is enabled then this can cause the kernel to incorrectly probe the generic designware PCIe platform driver instead of the Tegra194 designware PCIe driver. This causes a boot failure on Tegra194 because the necessary configuration to access the hardware is not performed. The order in which the compatible strings are populated in Device-Tree is not relevant in this case, because the kernel will attempt to probe the device as soon as a driver is loaded and if the generic designware PCIe driver is loaded first, then this driver will be probed first. Therefore, to fix this problem, remove the "snps,dw-pcie" string from the compatible string as we never want this driver to be probe on Tegra194. Fixes: 2602c32f15e7 ("arm64: tegra: Add P2U and PCIe controller nodes to Tegra194 DT") Signed-off-by: Jon Hunter <jonathanh@nvidia.com> Signed-off-by: Thierry Reding <treding@nvidia.com> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit f9f711efd441ad0d22874be49986d92121862335 ]

If the kernel configuration option CONFIG_PCIE_DW_PLAT_HOST is enabled
then this can cause the kernel to incorrectly probe the generic
designware PCIe platform driver instead of the Tegra194 designware PCIe
driver. This causes a boot failure on Tegra194 because the necessary
configuration to access the hardware is not performed.

The order in which the compatible strings are populated in Device-Tree
is not relevant in this case, because the kernel will attempt to probe
the device as soon as a driver is loaded and if the generic designware
PCIe driver is loaded first, then this driver will be probed first.
Therefore, to fix this problem, remove the "snps,dw-pcie" string from
the compatible string as we never want this driver to be probe on
Tegra194.

Fixes: 2602c32f15e7 ("arm64: tegra: Add P2U and PCIe controller nodes to Tegra194 DT")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>