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13 commits

Author SHA1 Message Date
Jiaxun Yang
1547951628 MIPS: Clear Cause.BD in instruction_pointer_set
[ Upstream commit 9d6e21ddf20293b3880ae55b9d14de91c5891c59 ]

Clear Cause.BD after we use instruction_pointer_set to override
EPC.

This can prevent exception_epc check against instruction code at
new return address.
It won't be considered as "in delay slot" after epc being overridden
anyway.

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 08:44:35 +01:00
Serge Semin
430cbbd160 mips: Fix max_mapnr being uninitialized on early stages
[ Upstream commit e1a9ae45736989c972a8d1c151bc390678ae6205 ]

max_mapnr variable is utilized in the pfn_valid() method in order to
determine the upper PFN space boundary. Having it uninitialized
effectively makes any PFN passed to that method invalid. That in its turn
causes the kernel mm-subsystem occasion malfunctions even after the
max_mapnr variable is actually properly updated. For instance,
pfn_valid() is called in the init_unavailable_range() method in the
framework of the calls-chain on MIPS:
setup_arch()
+-> paging_init()
    +-> free_area_init()
        +-> memmap_init()
            +-> memmap_init_zone_range()
                +-> init_unavailable_range()

Since pfn_valid() always returns "false" value before max_mapnr is
initialized in the mem_init() method, any flatmem page-holes will be left
in the poisoned/uninitialized state including the IO-memory pages. Thus
any further attempts to map/remap the IO-memory by using MMU may fail.
In particular it happened in my case on attempt to map the SRAM region.
The kernel bootup procedure just crashed on the unhandled unaligned access
bug raised in the __update_cache() method:

> Unhandled kernel unaligned access[#1]:
> CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.7.0-rc1-XXX-dirty #2056
> ...
> Call Trace:
> [<8011ef9c>] __update_cache+0x88/0x1bc
> [<80385944>] ioremap_page_range+0x110/0x2a4
> [<80126948>] ioremap_prot+0x17c/0x1f4
> [<80711b80>] __devm_ioremap+0x8c/0x120
> [<80711e0c>] __devm_ioremap_resource+0xf4/0x218
> [<808bf244>] sram_probe+0x4f4/0x930
> [<80889d20>] platform_probe+0x68/0xec
> ...

Let's fix the problem by initializing the max_mapnr variable as soon as
the required data is available. In particular it can be done right in the
paging_init() method before free_area_init() is called since all the PFN
zone boundaries have already been calculated by that time.

Cc: stable@vger.kernel.org
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:13:33 +01:00
Guenter Roeck
4536da25e4 MIPS: Add 'memory' clobber to csum_ipv6_magic() inline assembler
[ Upstream commit d55347bfe4e66dce2e1e7501e5492f4af3e315f8 ]

After 'lib: checksum: Use aligned accesses for ip_fast_csum and
csum_ipv6_magic tests' was applied, the test_csum_ipv6_magic unit test
started failing for all mips platforms, both little and bit endian.
Oddly enough, adding debug code into test_csum_ipv6_magic() made the
problem disappear.

The gcc manual says:

"The "memory" clobber tells the compiler that the assembly code performs
 memory reads or writes to items other than those listed in the input
 and output operands (for example, accessing the memory pointed to by one
 of the input parameters)
"

This is definitely the case for csum_ipv6_magic(). Indeed, adding the
'memory' clobber fixes the problem.

Cc: Charlie Jenkins <charlie@rivosinc.com>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Charlie Jenkins <charlie@rivosinc.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:13:28 +01:00
Xi Ruoyao
ff49d5abe8 mips: Call lose_fpu(0) before initializing fcr31 in mips_set_personality_nan
commit 59be5c35850171e307ca5d3d703ee9ff4096b948 upstream.

If we still own the FPU after initializing fcr31, when we are preempted
the dirty value in the FPU will be read out and stored into fcr31,
clobbering our setting.  This can cause an improper floating-point
environment after execve().  For example:

    zsh% cat measure.c
    #include <fenv.h>
    int main() { return fetestexcept(FE_INEXACT); }
    zsh% cc measure.c -o measure -lm
    zsh% echo $((1.0/3)) # raising FE_INEXACT
    0.33333333333333331
    zsh% while ./measure; do ; done
    (stopped in seconds)

Call lose_fpu(0) before setting fcr31 to prevent this.

Closes: https://lore.kernel.org/linux-mips/7a6aa1bbdbbe2e63ae96ff163fab0349f58f1b9e.camel@xry111.site/
Fixes: 9b26616c8d9d ("MIPS: Respect the ISA level in FCSR handling")
Cc: stable@vger.kernel.org
Signed-off-by: Xi Ruoyao <xry111@xry111.site>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 12:13:07 +01:00
Christophe JAILLET
82d671052b MIPS: Alchemy: Fix an out-of-bound access in db1550_dev_setup()
[ Upstream commit 3c1e5abcda64bed0c7bffa65af2316995f269a61 ]

When calling spi_register_board_info(),

Fixes: f869d42e580f ("MIPS: Alchemy: Improved DB1550 support, with audio and serial busses.")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:12:48 +01:00
Christophe JAILLET
95d5b70a46 MIPS: Alchemy: Fix an out-of-bound access in db1200_dev_setup()
[ Upstream commit 89c4b588d11e9acf01d604de4b0c715884f59213 ]

When calling spi_register_board_info(), we should pass the number of
elements in 'db1200_spi_devs', not 'db1200_i2c_devs'.

Fixes: 63323ec54a7e ("MIPS: Alchemy: Extended DB1200 board support.")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:12:48 +01:00
Serge Semin
031b728384 mips: Fix incorrect max_low_pfn adjustment
[ Upstream commit 0f5cc249ff73552d3bd864e62f85841dafaa107d ]

max_low_pfn variable is incorrectly adjusted if the kernel is built with
high memory support and the later is detected in a running system, so the
memory which actually can be directly mapped is getting into the highmem
zone. See the ZONE_NORMAL range on my MIPS32r5 system:

> Zone ranges:
>   DMA      [mem 0x0000000000000000-0x0000000000ffffff]
>   Normal   [mem 0x0000000001000000-0x0000000007ffffff]
>   HighMem  [mem 0x0000000008000000-0x000000020fffffff]

while the zones are supposed to look as follows:

> Zone ranges:
>   DMA      [mem 0x0000000000000000-0x0000000000ffffff]
>   Normal   [mem 0x0000000001000000-0x000000001fffffff]
>   HighMem  [mem 0x0000000020000000-0x000000020fffffff]

Even though the physical memory within the range [0x08000000;0x20000000]
belongs to MMIO on our system, we don't really want it to be considered as
high memory since on MIPS32 that range still can be directly mapped.

Note there might be other problems caused by the max_low_pfn variable
misconfiguration. For instance high_memory variable is initialize with
virtual address corresponding to the max_low_pfn PFN, and by design it
must define the upper bound on direct map memory, then end of the normal
zone. That in its turn potentially may cause problems in accessing the
memory by means of the /dev/mem and /dev/kmem devices.

Let's fix the discovered misconfiguration then. It turns out the commit
a94e4f24ec83 ("MIPS: init: Drop boot_mem_map") didn't introduce the
max_low_pfn adjustment quite correct. If the kernel is built with high
memory support and the system is equipped with high memory, the
max_low_pfn variable will need to be initialized with PFN of the most
upper directly reachable memory address so the zone normal would be
correctly setup. On MIPS that PFN corresponds to PFN_DOWN(HIGHMEM_START).
If the system is built with no high memory support and one is detected in
the running system, we'll just need to adjust the max_pfn variable to
discard the found high memory from the system and leave the max_low_pfn as
is, since the later will be less than PFN_DOWN(HIGHMEM_START) anyway by
design of the for_each_memblock() loop performed a bit early in the
bootmem_init() method.

Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:12:48 +01:00
Serge Semin
2f88c12e90 mips: dmi: Fix early remap on MIPS32
[ Upstream commit 0d0a3748a2cb38f9da1f08d357688ebd982eb788 ]

dmi_early_remap() has been defined as ioremap_cache() which on MIPS32 gets
to be converted to the VM-based mapping. DMI early remapping is performed
at the setup_arch() stage with no VM available. So calling the
dmi_early_remap() for MIPS32 causes the system to crash at the early boot
time. Fix that by converting dmi_early_remap() to the uncached remapping
which is always available on both 32 and 64-bits MIPS systems.

Note this change shall not cause any regressions on the current DMI
support implementation because on the early boot-up stage neither MIPS32
nor MIPS64 has the cacheable ioremapping support anyway.

Fixes: be8fa1cb444c ("MIPS: Add support for Desktop Management Interface (DMI)")
Signed-off-by: Serge Semin <fancer.lancer@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:12:48 +01:00
Greg Kroah-Hartman
34e0e18d41 Revert "MIPS: Loongson64: Enable DMA noncoherent support"
This reverts commit 3ee7e2faef87594228eb2622f8c25c0495ea50a1 which is
commit edc0378eee00200a5bedf1bb9f00ad390e0d1bd4 upstream.

There are reports of this causing build issues, so revert it from the
5.10.y tree for now.

Reported-by: Salvatore Bonaccorso <carnil@debian.org>
Link: https://lore.kernel.org/r/ZZE1X8m5PXJExffG@eldamar.lan
Cc: Jiaxun Yang <jiaxun.yang@flygoat.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 12:12:04 +01:00
Jiaxun Yang
191edae40a MIPS: Loongson64: Enable DMA noncoherent support
commit edc0378eee00200a5bedf1bb9f00ad390e0d1bd4 upstream.

There are some Loongson64 systems come with broken coherent DMA
support, firmware will set a bit in boot_param and pass nocoherentio
in cmdline.

However nonconherent support was missed out when spin off Loongson-2EF
form Loongson64, and that boot_param change never made itself into
upstream.

Support DMA noncoherent properly to get those systems working.

Cc: stable@vger.kernel.org
Fixes: 71e2f4dd5a65 ("MIPS: Fork loongson2ef from loongson64")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 12:11:46 +01:00
Jiaxun Yang
1e2ffe3005 MIPS: Loongson64: Reserve vgabios memory on boot
commit 8f7aa77a463f47c9e00592d02747a9fcf2271543 upstream.

vgabios is passed from firmware to kernel on Loongson64 systems.
Sane firmware will keep this pointer in reserved memory space
passed from the firmware but insane firmware keeps it in low
memory before kernel entry that is not reserved.

Previously kernel won't try to allocate memory from low memory
before kernel entry on boot, but after converting to memblock
it will do that.

Fix by resversing those memory on early boot.

Cc: stable@vger.kernel.org
Fixes: a94e4f24ec83 ("MIPS: init: Drop boot_mem_map")
Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-11-18 12:11:46 +01:00
Huacai Chen
a950ee6028 MIPS: KVM: Fix a build warning about variable set but not used
[ Upstream commit 83767a67e7b6a0291cde5681ec7e3708f3f8f877 ]

After commit 411740f5422a ("KVM: MIPS/MMU: Implement KVM_CAP_SYNC_MMU")
old_pte is no longer used in kvm_mips_map_page(). So remove it to fix a
build warning about variable set but not used:

   arch/mips/kvm/mmu.c: In function 'kvm_mips_map_page':
>> arch/mips/kvm/mmu.c:701:29: warning: variable 'old_pte' set but not used [-Wunused-but-set-variable]
     701 |         pte_t *ptep, entry, old_pte;
         |                             ^~~~~~~

Cc: stable@vger.kernel.org
Fixes: 411740f5422a960 ("KVM: MIPS/MMU: Implement KVM_CAP_SYNC_MMU")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202310070530.aARZCSfh-lkp@intel.com/
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-18 12:10:56 +01:00
Gabriel2392
7ed7ee9edf Import A536BXXU9EXDC 2024-06-15 16:02:09 -03:00