Tegra DRM doesn't support display on Tegra234 and later, so make sure
not to remove any existing framebuffers in that case.
v2: - add comments explaining how this situation can come about
- clear DRIVER_MODESET and DRIVER_ATOMIC feature bits
Fixes: 6848c291a5 ("drm/aperture: Convert drivers to aperture interfaces")
Signed-off-by: Thierry Reding <treding@nvidia.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20240223150333.1401582-1-thierry.reding@gmail.com
The hash_pa8 and hashed_bit values in denorm_addr_df4_np2() are
currently defined as u8 types. These variables represent single bits.
'hash_pa8' is set based on logical AND operations using masks with more
than 8 bits. So the calculated value will not fit in this variable. It
will always be '0'. The 'hash_pa8' check later in the function will fail
which produces incorrect results for some cases.
Change these variables to bool type. This clarifies that they are
single bit values. Also, this allows the compiler to ensure they hold
the proper results. Remove an unnecessary shift operation.
[ bp: Remove the unnecessary brackets in the else-branch of the
hash_pa8 assignment. ]
Fixes: 3f3174996b ("RAS: Introduce AMD Address Translation Library")
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20240222165449.23582-1-yazen.ghannam@amd.com
As the TWL6030 chip is the main power controller here, declare
it as system-power-controller
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Message-ID: <20240217082007.3238948-5-andreas@kemnade.info>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Configure the TWL6032 as system power controller to let the device
power off.
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Message-ID: <20240217082007.3238948-4-andreas@kemnade.info>
Signed-off-by: Tony Lindgren <tony@atomide.com>
early_top_pgt[] is assigned from code that executes from a 1:1 mapping
so it cannot use a plain access from C. Replace the use of
fixup_pointer() with RIP_REL_REF(), which is better and simpler.
For legibility and to align with the code that populates the lower page
table levels, statically initialize the root level page table with an
entry pointing to level3_kernel_pgt[], and overwrite it when needed to
enable 5-level paging.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-24-ardb+git@google.com
The early statically allocated page tables are populated from code that
executes from a 1:1 mapping so it cannot use plain accesses from C.
Replace the use of fixup_pointer() with RIP_REL_REF(), which is better
and simpler.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-23-ardb+git@google.com
'__supported_pte_mask' is accessed from code that executes from a 1:1
mapping so it cannot use a plain access from C. Replace the use of
fixup_pointer() with RIP_REL_REF(), which is better and simpler.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-22-ardb+git@google.com
early_dynamic_pgts[] and next_early_pgt are accessed from code that
executes from a 1:1 mapping so it cannot use a plain access from C.
Replace the use of fixup_pointer() with RIP_REL_REF(), which is better
and simpler.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-21-ardb+git@google.com
'phys_base' is assigned from code that executes from a 1:1 mapping so it
cannot use a plain access from C. Replace the use of fixup_pointer()
with RIP_REL_REF(), which is better and simpler.
While at it, move the assignment to before the addition of the SME mask
so there is no need to subtract it again, and drop the unnecessary
addition ('phys_base' is statically initialized to 0x0)
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-20-ardb+git@google.com
There are two code paths in the startup code to program an IDT: one that
runs from the 1:1 mapping and one that runs from the virtual kernel
mapping. Currently, these are strictly separate because fixup_pointer()
is used on the 1:1 path, which will produce the wrong value when used
while executing from the virtual kernel mapping.
Switch to RIP_REL_REF() so that the two code paths can be merged. Also,
move the GDT and IDT descriptors to the stack so that they can be
referenced directly, rather than via RIP_REL_REF().
Rename startup_64_setup_env() to startup_64_setup_gdt_idt() while at it,
to make the call from assembler self-documenting.
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20240221113506.2565718-19-ardb+git@google.com
Move the pending urls back to https:// and mark the ones that are no
longer accessible (http or https) as defunct.
Signed-off-by: Nishanth Menon <nm@ti.com>
Message-ID: <20240109195500.3833121-1-nm@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
abb_{mpu,ivahd,dspeve,gpu} have 'reg' so they must have unit address to fix dtc
W=1 warnings:
Warning (unit_address_vs_reg): /ocp/regulator-abb-mpu: node has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): /ocp/regulator-abb-ivahd: node has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): /ocp/regulator-abb-dspeve: node has a reg or ranges property, but no unit name
Warning (unit_address_vs_reg): /ocp/regulator-abb-gpu: node has a reg or ranges property, but no unit name
Signed-off-by: Romain Naour <romain.naour@skf.com>
Message-ID: <20240123085551.733155-3-romain.naour@smile.fr>
Signed-off-by: Tony Lindgren <tony@atomide.com>
It seems that if userspace provides a correct IFA_TARGET_NETNSID value
but no IFA_ADDRESS and IFA_LOCAL attributes, inet6_rtm_getaddr()
returns -EINVAL with an elevated "struct net" refcount.
Fixes: 6ecf4c37eb ("ipv6: enable IFA_TARGET_NETNSID for RTM_GETADDR")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
sys_32k_ck node have 'reg' so it must have unit address to fix dtc
W=1 warnings:
Warning (unit_address_vs_reg): /ocp/interconnect@4a000000/segment@0/target-module@2000/scm@0/scm_conf@0/clocks/clock-sys-32k: node has a reg or ranges property, but no unit name
Signed-off-by: Romain Naour <romain.naour@skf.com>
Message-ID: <20240123085551.733155-2-romain.naour@smile.fr>
Signed-off-by: Tony Lindgren <tony@atomide.com>
phy_gmii_sel node have 'reg' so it must have unit address to fix dtc
W=1 warnings:
Warning (unit_address_vs_reg): /ocp/interconnect@4a000000/segment@0/target-module@2000/scm@0/scm_conf@0/phy-gmii-sel: node has a reg or ranges property, but no unit name
Signed-off-by: Romain Naour <romain.naour@skf.com>
Message-ID: <20240123085551.733155-1-romain.naour@smile.fr>
Signed-off-by: Tony Lindgren <tony@atomide.com>
MHI expects the controller configs to be const, and all of the other ones
in this file already are, so constify modem_telit_fn980_hw_v1_config.
Signed-off-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20240222-mhi-const-bus-mhi-host-pci_generic-v1-1-d4c9b0b0a7a5@quicinc.com
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Eric Dumazet says:
====================
rtnetlink: reduce RTNL pressure for dumps
This series restarts the conversion of rtnl dump operations
to RCU protection, instead of requiring RTNL.
In this new attempt (prior one failed in 2011), I chose to
allow a gradual conversion of selected operations.
After this series, "ip -6 addr" and "ip -4 ro" no longer
need to acquire RTNL.
I refrained from changing inet_dump_ifaddr() and inet6_dump_addr()
to avoid merge conflicts because of two fixes in net tree.
I also started the work for "ip link" future conversion.
v2: rtnl_fill_link_ifmap() always emit IFLA_MAP (Jiri Pirko)
Added "nexthop: allow nexthop_mpath_fill_node()
to be called without RTNL" to avoid a lockdep splat (Ido Schimmel)
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to be able to run rtnl_fill_ifinfo() under RCU protection
instead of RTNL in the future.
dev->name_node items are already rcu protected.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use READ_ONCE() to read the following device fields:
dev->mem_start
dev->mem_end
dev->base_addr
dev->irq
dev->dma
dev->if_port
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No longer hold RTNL while calling inet_dump_fib().
Also change return value for a completed dump:
Returning 0 instead of skb->len allows NLMSG_DONE
to be appended to the skb. User space does not have
to call us again to get a standalone NLMSG_DONE marker.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
nexthop_mpath_fill_node() will be potentially called
from contexts holding rcu_lock instead of RTNL.
Suggested-by: Ido Schimmel <idosch@nvidia.com>
Link: https://lore.kernel.org/all/ZdZDWVdjMaQkXBgW@shredder/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new field into struct fib_dump_filter, to let callers
tell if they use RTNL locking or RCU.
This is used in the following patch, when inet_dump_fib()
no longer holds RTNL.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No longer hold RTNL while calling inet6_dump_ifinfo()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similarly to RTNL_FLAG_DOIT_UNLOCKED, this new flag
allows dump operations registered via rtnl_register()
or rtnl_register_module() to opt-out from RTNL protection.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit af65bdfce9 ("[NETLINK]: Switch cb_lock spinlock
to mutex and allow to override it"), Patrick McHardy used
a common mutex to protect both nlk->cb and the dump() operations.
The override is used for rtnl dumps, registered with
rntl_register() and rntl_register_module().
We want to be able to opt-out some dump() operations
to not acquire RTNL, so we need to protect nlk->cb
with a per socket mutex.
This patch renames nlk->cb_def_mutex to nlk->nl_cb_mutex
The optional pointer to the mutex used to protect dump()
call is stored in nlk->dump_cb_mutex
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__netlink_dump_start() releases nlk->cb_mutex right before
calling netlink_dump() which grabs it again.
This seems dangerous, even if KASAN did not bother yet.
Add a @lock_taken parameter to netlink_dump() to let it
grab the mutex if called from netlink_recvmsg() only.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__netlink_diag_dump() returns 1 if the dump is not complete,
zero if no error occurred.
If err variable is zero, this means the dump is complete:
We should not return skb->len in this case, but 0.
This allows NLMSG_DONE to be appended to the skb.
User space does not have to call us again only to get NLMSG_DONE.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Prepare inet6_dump_ifinfo() to run with RCU protection
instead of RTNL and use for_each_netdev_dump() interface.
Also properly return 0 at the end of a dump, avoiding
an extra recvmsg() system call and RTNL acquisition.
Note that RTNL-less dumps need core changes, coming later
in the series.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to use RCU protection instead of RTNL
for inet6_fill_ifinfo().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to no longer hold RTNL while calling inet6_fill_ifla6_attrs()
in the future. Add needed READ_ONCE()/WRITE_ONCE() annotations.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want to be able to run rtnl_fill_ifinfo() under RCU protection
instead of RTNL in the future.
This patch prepares dev_get_iflink() and nla_put_iflink()
to run either with RTNL or RCU held.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jérémie Dautheribes says:
====================
Add support for TI DP83826 configuration
This short patch series introduces the possibility of overriding
some parameters which are latched by default by hardware straps on the
TI DP83826 PHY.
The settings that can be overridden include:
- Configuring the PHY in either MII mode or RMII mode.
- When in RMII mode, configuring the PHY in RMII slave mode or RMII
master mode.
The RMII master/slave mode is TI-specific and determines whether the PHY
operates from a 25MHz reference clock (master mode) or from a 50MHz
reference clock (slave mode).
While these features should be supported by all the TI DP8382x family,
I have only been able to test them on TI DP83826 hardware. Therefore,
support has been added specifically for this PHY in this patch series.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The TI DP83826 PHY can operate between two RMII modes:
- master mode (PHY operates from a 25MHz clock reference)
- slave mode (PHY operates from a 50MHz clock reference)
By default, the operation mode is configured by hardware straps.
Add support to configure the operation mode from within the driver.
Signed-off-by: Jérémie Dautheribes <jeremie.dautheribes@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The TI DP83826 PHY can operate in either MII mode or RMII mode.
By default, it is configured by straps.
It can also be configured by writing to the bit 5 of register 0x17 - RMII
and Status Register (RCSR).
When phydev->interface is rmii, rmii mode must be enabled, otherwise
mii mode must be set.
This prevents misconfiguration of hw straps.
Signed-off-by: Jérémie Dautheribes <jeremie.dautheribes@bootlin.com>
Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add property ti,rmii-mode to support selecting the RMII operation mode
between:
- master mode (PHY operates from a 25MHz clock reference)
- slave mode (PHY operates from a 50MHz clock reference)
If not set, the operation mode is configured by hardware straps.
Signed-off-by: Jérémie Dautheribes <jeremie.dautheribes@bootlin.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement bridge port isolation for KSZ switches. Enabling the isolation
of switch ports from each other while maintaining connectivity with the
CPU and other forwarding ports. For instance, to isolate swp1 and swp2
from each other, use the following commands:
- bridge link set dev swp1 isolated on
- bridge link set dev swp2 isolated on
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Arun Ramadoss <arun.ramadoss@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Test that we keep GRO flag in sync when XDP is disabled while
the device is closed.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
veth sets NETIF_F_GRO automatically when XDP is enabled,
because both features use the same NAPI machinery.
The logic to clear NETIF_F_GRO sits in veth_disable_xdp() which
is called both on ndo_stop and when XDP is turned off.
To avoid the flag from being cleared when the device is brought
down, the clearing is skipped when IFF_UP is not set.
Bringing the device down should indeed not modify its features.
Unfortunately, this means that clearing is also skipped when
XDP is disabled _while_ the device is down. And there's nothing
on the open path to bring the device features back into sync.
IOW if user enables XDP, disables it and then brings the device
up we'll end up with a stray GRO flag set but no NAPI instances.
We don't depend on the GRO flag on the datapath, so the datapath
won't crash. We will crash (or hang), however, next time features
are sync'ed (either by user via ethtool or peer changing its config).
The GRO flag will go away, and veth will try to disable the NAPIs.
But the open path never created them since XDP was off, the GRO flag
was a stray. If NAPI was initialized before we'll hang in napi_disable().
If it never was we'll crash trying to stop uninitialized hrtimer.
Move the GRO flag updates to the XDP enable / disable paths,
instead of mixing them with the ndo_open / ndo_close paths.
Fixes: d3256efd8e ("veth: allow enabling NAPI even without XDP")
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: syzbot+039399a9b96297ddedca@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some of Infineon SPI NOR flash devices support hybrid sector layout that
overlays 4KB sectors on a 256KB sector and SPI NOR framework recognizes
that by parsing SMPT and construct params->erase_map. The hybrid sector
layout is similar to CFI flash devices that have small sectors on top
and/or bottom address. In case of CFI flash devices, the erase map
information is parsed through CFI table and populated into
mtd->eraseregions so that users can create MTD partitions that aligned
with small sector boundaries. This patch provides the same capability to
SPI NOR flash devices that have non-uniform erase map.
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/35d0962986e493b06c13bdf7ada8130a9966dc02.1708404584.git.Takahiro.Kuwano@infineon.com
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Introduce n_regions in spi_nor_erase_map structure and remove
SNOR_LAST_REGION flag. Loop logics that depend on the flag are also
reworked to use n_regions as loop condition.
Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Suggested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Suggested-by: Michael Walle <mwalle@kernel.org>
Reviewed-by: Michael Walle <mwalle@kernel.org>
Link: https://lore.kernel.org/r/eded84294bd81e966d6f423e578fc2cfb9a4a5b6.1708404584.git.Takahiro.Kuwano@infineon.com
[ta: update spi_nor_init_erase_cmd_list() and break the for loop sooner.]
Signed-off-by: Tudor Ambarus <tudor.ambarus@linaro.org>
For the clksel clocks we are still using the legacy ti,bit-shift property
instead of the standard reg property. We can now use the reg property, so
let's do that for the clksel clocks.
To add the reg property, we switch to use #address-cells = <1>.
For now let's not update the clock-dss-tv-fck as it seems to share the same
register bit as the clock-dss-96m-fck and would introduce more warnings.
Cc: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Tony Lindgren <tony@atomide.com>
For the clksel clocks we are still using the legacy ti,bit-shift property
instead of the standard reg property. We can now use the reg property, so
let's do that for the clksel clocks.
To add the reg property, we switch to use #address-cells = <1>.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Because of legacy reasons, the TI clksel composite clocks can have
overlapping reg properties, and use a custom ti,bit-shift property.
For the clksel clocks we can start using of the standard reg property
instead of the custom ti,bit-shift property.
To do this, let's add a ti_clk_get_legacy_bit_shift() helper, and make
ti_clk_get_reg_addr() populate the clock bit offset.
This makes it possible to update the devicetree files to use the reg
property one clock at a time.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
In order to use #address-cells = <1> and start making use of the
standard reg property, let's prepare things to ignore the possible
address in the clock node name.
Unless the clock-output-names property is used, the legacy clocks still
fall back to matching the clock data based on the node name.
We use cleanup.h to simplify the return path for freeing tmp.
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
After a couple recent changes in LLVM, there is a warning (or error with
CONFIG_WERROR=y or W=e) from the compile time fortify source routines,
specifically the memset() in copy_to_user_tmpl().
In file included from net/xfrm/xfrm_user.c:14:
...
include/linux/fortify-string.h:438:4: error: call to '__write_overflow_field' declared with 'warning' attribute: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Werror,-Wattribute-warning]
438 | __write_overflow_field(p_size_field, size);
| ^
1 error generated.
While ->xfrm_nr has been validated against XFRM_MAX_DEPTH when its value
is first assigned in copy_templates() by calling validate_tmpl() first
(so there should not be any issue in practice), LLVM/clang cannot really
deduce that across the boundaries of these functions. Without that
knowledge, it cannot assume that the loop stops before i is greater than
XFRM_MAX_DEPTH, which would indeed result a stack buffer overflow in the
memset().
To make the bounds of ->xfrm_nr clear to the compiler and add additional
defense in case copy_to_user_tmpl() is ever used in a path where
->xfrm_nr has not been properly validated against XFRM_MAX_DEPTH first,
add an explicit bound check and early return, which clears up the
warning.
Cc: stable@vger.kernel.org
Link: https://github.com/ClangBuiltLinux/linux/issues/1985
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmXb0T4eHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiG5YQH/3eCV90sNGch0Y94
8rtTdqFrVx7QPNl0pz+Mo6OUIKUUHvTuwime16ckLxG+3x2Y3I0MjP1edd1NB99C
Kje//JTpaZBPpTZ/jY4u8B1Shov2Drdx/J4NFnE/9rG6yXzKQBtvON/xAxXDCVHT
mLhst2LR0FeCSMk9jAX6CoqUPEgwlylNyAetKxaDQgoHl4GTZC7FDO17WxyjpIxe
1rVHsrV9Eq8kD4uxrzpTYWgZrwTObPmlZjvefa1JfzSwRNABIBJj/C1nra1Zc1oi
b7xVaXS1cMOxrtuuG00fmHsPnWivu0tuND7H3/yLd1mRCZAPSsVbVvrI/KNtoeV4
1euINlY=
=7IFt
-----END PGP SIGNATURE-----
Merge v6.8-rc6 into drm-next
Thomas Zimmermann asked to backmerge -rc6 for drm-misc branches,
there's a few same-area-changed conflicts (xe and amdgpu mostly) that
are getting a bit too annoying.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
The next timer (re-)evaluation, with the purpose of entering/updating
the dyntick mode, can happen from 3 sites and none of them are relevant
while the CPU is offline:
1) The idle loop:
a) From the quick check helping the cpuidle governor to heuristically
predict the best C-state.
b) While stopping the tick.
But if the CPU is offline, the tick has been cancelled and there is
consequently no need to further stop the tick.
2) Remote expiry: when a CPU remotely expires global timers on behalf of
another CPU, the latter target's next timer is re-evaluated
afterwards. However remote expîry doesn't happen on offline CPUs.
3) IRQ exit: on nohz_full mode, the tick is (re-)evaluated on IRQ exit.
But full dynticks is disabled on offline CPUs.
Therefore it is safe to assume that no next dyntick timer lookup can
be performed on offline CPUs.
Assert this expectation to report any surprise.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240225225508.11587-17-frederic@kernel.org
The timekeeping duty is handed over from the outgoing CPU on stop
machine, then the oneshot tick is stopped right after. Therefore it's
guaranteed that the current CPU isn't the timekeeper upon its last call
to idle.
Besides, calling tick_nohz_idle_stop_tick() while the dying CPU goes
into idle suggests that the tick is going to be stopped while it is
actually stopped already from the appropriate CPU hotplug state.
Remove the confusing call and the obsolete case handling and convert it
to a sanity check that verifies the above assumption.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240225225508.11587-16-frederic@kernel.org
The timekeeping duty is handed over from the outgoing CPU within stop
machine. This works well if CONFIG_NO_HZ_COMMON=n or the tick is in
high-res mode. However in low-res dynticks mode, the tick isn't
cancelled until the clockevent is shut down, which can happen later. The
tick may therefore fire again once IRQs are re-enabled on stop machine
and until IRQs are disabled for good upon the last call to idle.
That's so many opportunities for a timekeeper to go idle and the
outgoing CPU to take over that duty. This is why
tick_nohz_idle_stop_tick() is called one last time on idle if the CPU
is seen offline: so that the timekeeping duty is handed over again in
case the CPU has re-taken the duty.
This means there are two timekeeping handovers on CPU down hotplug with
different undocumented constraints and purposes:
1) A handover on stop machine for !dynticks || highres. All online CPUs
are guaranteed to be non-idle and the timekeeping duty can be safely
handed-over. The hrtimer tick is cancelled so it is guaranteed that in
dynticks mode the outgoing CPU won't take again the duty.
2) A handover on last idle call for dynticks && lowres. Setting the
duty to TICK_DO_TIMER_NONE makes sure that a CPU will take over the
timekeeping.
Prepare for consolidating the handover to a single place (the first one)
with shutting down the low-res tick as well from
tick_cancel_sched_timer() as well. This will simplify the handover and
unify the tick cancellation between high-res and low-res.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20240225225508.11587-15-frederic@kernel.org
