user/sven/linux.git/arch/mips/kernel, branch v4.9.254

MIPS: relocatable: fix possible boot hangup with KASLR enabled

2021-01-23T14:38:16Z

commit 69e976831cd53f9ba304fd20305b2025ecc78eab upstream. LLVM-built Linux triggered a boot hangup with KASLR enabled. arch/mips/kernel/relocate.c:get_random_boot() uses linux_banner, which is a string constant, as a random seed, but accesses it as an array of unsigned long (in rotate_xor()). When the address of linux_banner is not aligned to sizeof(long), such access emits unaligned access exception and hangs the kernel. Use PTR_ALIGN() to align input address to sizeof(long) and also align down the input length to prevent possible access-beyond-end. Fixes: 405bc8fd12f5 ("MIPS: Kernel: Implement KASLR using CONFIG_RELOCATABLE") Cc: stable@vger.kernel.org # 4.7+ Signed-off-by: Alexander Lobakin Tested-by: Nathan Chancellor Reviewed-by: Kees Cook Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

MIPS: BMIPS: Also call bmips_cpu_setup() for secondary cores

2020-09-12T09:47:33Z

[ Upstream commit e14f633b66902615cf7faa5d032b45ab8b6fb158 ] The initialization done by bmips_cpu_setup() typically affects both threads of a given core, on 7435 which supports 2 cores and 2 threads, logical CPU number 2 and 3 would not run this initialization. Fixes: 738a3f79027b ("MIPS: BMIPS: Add early CPU initialization code") Signed-off-by: Florian Fainelli Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: CPU#0 is not hotpluggable

2020-08-21T09:02:08Z

commit 9cce844abf07b683cff5f0273977d5f8d0af94c7 upstream. Now CPU#0 is not hotpluggable on MIPS, so prevent to create /sys/devices /system/cpu/cpu0/online which confuses some user-space tools. Cc: stable@vger.kernel.org Signed-off-by: Huacai Chen Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

MIPS: Fix build for LTS kernel caused by backporting lpj adjustment

2020-07-22T07:10:53Z

Commit ed26aacfb5f71eecb20a ("mips: Add udelay lpj numbers adjustment") has backported to 4.4~5.4, but the "struct cpufreq_freqs" (and also the cpufreq notifier machanism) of 4.4~4.19 are different from the upstream kernel. These differences cause build errors, and this patch can fix the build. Cc: Serge Semin Cc: Stable # 4.4/4.9/4.14/4.19 Signed-off-by: Huacai Chen Signed-off-by: Greg Kroah-Hartman

MIPS: Add missing EHB in mtc0 -> mfc0 sequence for DSPen

2020-07-09T07:35:56Z

commit fcec538ef8cca0ad0b84432235dccd9059c8e6f8 upstream. This resolves the hazard between the mtc0 in the change_c0_status() and the mfc0 in configure_exception_vector(). Without resolving this hazard configure_exception_vector() could read an old value and would restore this old value again. This would revert the changes change_c0_status() did. I checked this by printing out the read_c0_status() at the end of per_cpu_trap_init() and the ST0_MX is not set without this patch. The hazard is documented in the MIPS Architecture Reference Manual Vol. III: MIPS32/microMIPS32 Privileged Resource Architecture (MD00088), rev 6.03 table 8.1 which includes: Producer | Consumer | Hazard ----------|----------|---------------------------- mtc0 | mfc0 | any coprocessor 0 register I saw this hazard on an Atheros AR9344 rev 2 SoC with a MIPS 74Kc CPU. There the change_c0_status() function would activate the DSPen by setting ST0_MX in the c0_status register. This was reverted and then the system got a DSP exception when the DSP registers were saved in save_dsp() in the first process switch. The crash looks like this: [ 0.089999] Mount-cache hash table entries: 1024 (order: 0, 4096 bytes, linear) [ 0.097796] Mountpoint-cache hash table entries: 1024 (order: 0, 4096 bytes, linear) [ 0.107070] Kernel panic - not syncing: Unexpected DSP exception [ 0.113470] Rebooting in 1 seconds.. We saw this problem in OpenWrt only on the MIPS 74Kc based Atheros SoCs, not on the 24Kc based SoCs. We only saw it with kernel 5.4 not with kernel 4.19, in addition we had to use GCC 8.4 or 9.X, with GCC 8.3 it did not happen. In the kernel I bisected this problem to commit 9012d011660e ("compiler: allow all arches to enable CONFIG_OPTIMIZE_INLINING"), but when this was reverted it also happened after commit 172dcd935c34b ("MIPS: Always allocate exception vector for MIPSr2+"). Commit 0b24cae4d535 ("MIPS: Add missing EHB in mtc0 -> mfc0 sequence.") does similar changes to a different file. I am not sure if there are more places affected by this problem. Signed-off-by: Hauke Mehrtens Cc: Signed-off-by: Thomas Bogendoerfer Signed-off-by: Greg Kroah-Hartman

MIPS: Fix IRQ tracing when call handle_fpe() and handle_msa_fpe()

2020-06-20T08:24:18Z

[ Upstream commit 31e1b3efa802f97a17628dde280006c4cee4ce5e ] Register "a1" is unsaved in this function, when CONFIG_TRACE_IRQFLAGS is enabled, the TRACE_IRQS_OFF macro will call trace_hardirqs_off(), and this may change register "a1". The changed register "a1" as argument will be send to do_fpe() and do_msa_fpe(). Signed-off-by: YuanJunQing Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

mips: Add udelay lpj numbers adjustment

2020-06-20T08:24:17Z

[ Upstream commit ed26aacfb5f71eecb20a51c4467da440cb719d66 ] Loops-per-jiffies is a special number which represents a number of noop-loop cycles per CPU-scheduler quantum - jiffies. As you understand aside from CPU-specific implementation it depends on the CPU frequency. So when a platform has the CPU frequency fixed, we have no problem and the current udelay interface will work just fine. But as soon as CPU-freq driver is enabled and the cores frequency changes, we'll end up with distorted udelay's. In order to fix this we have to accordinly adjust the per-CPU udelay_val (the same as the global loops_per_jiffy) number. This can be done in the CPU-freq transition event handler. We subscribe to that event in the MIPS arch time-inititalization method. Co-developed-by: Alexey Malahov Signed-off-by: Alexey Malahov Signed-off-by: Serge Semin Reviewed-by: Jiaxun Yang Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Arnd Bergmann Cc: Rob Herring Cc: devicetree@vger.kernel.org Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

mips: cm: Fix an invalid error code of INTVN_*_ERR

2020-06-20T08:24:16Z

[ Upstream commit 8a0efb8b101665a843205eab3d67ab09cb2d9a8d ] Commit 3885c2b463f6 ("MIPS: CM: Add support for reporting CM cache errors") adds cm2_causes[] array with map of error type ID and pointers to the short description string. There is a mistake in the table, since according to MIPS32 manual CM2_ERROR_TYPE = {17,18} correspond to INTVN_WR_ERR and INTVN_RD_ERR, while the table claims they have {0x17,0x18} codes. This is obviously hex-dec copy-paste bug. Moreover codes {0x18 - 0x1a} indicate L2 ECC errors. Fixes: 3885c2b463f6 ("MIPS: CM: Add support for reporting CM cache errors") Signed-off-by: Serge Semin Cc: Alexey Malahov Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Arnd Bergmann Cc: Rob Herring Cc: linux-pm@vger.kernel.org Cc: devicetree@vger.kernel.org Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Truncate link address into 32bit for 32bit kernel

2020-06-20T08:24:16Z

[ Upstream commit ff487d41036035376e47972c7c522490b839ab37 ] LLD failed to link vmlinux with 64bit load address for 32bit ELF while bfd will strip 64bit address into 32bit silently. To fix LLD build, we should truncate load address provided by platform into 32bit for 32bit kernel. Signed-off-by: Jiaxun Yang Link: https://github.com/ClangBuiltLinux/linux/issues/786 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=25784 Reviewed-by: Fangrui Song Reviewed-by: Kees Cook Tested-by: Nathan Chancellor Cc: Maciej W. Rozycki Tested-by: Nick Desaulniers Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin

MIPS: Make sparse_init() using top-down allocation

2020-06-20T08:24:15Z

[ Upstream commit 269b3a9ac538c4ae87f84be640b9fa89914a2489 ] In the current code, if CONFIG_SWIOTLB is set, when failed to get IO TLB memory from the low pages by plat_swiotlb_setup(), it may lead to the boot process failed with kernel panic. (1) On the Loongson and SiByte platform arch/mips/loongson64/dma.c arch/mips/sibyte/common/dma.c void __init plat_swiotlb_setup(void) { swiotlb_init(1); } kernel/dma/swiotlb.c void __init swiotlb_init(int verbose) { ... vstart = memblock_alloc_low(PAGE_ALIGN(bytes), PAGE_SIZE); if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose)) return; ... pr_warn("Cannot allocate buffer"); no_iotlb_memory = true; } phys_addr_t swiotlb_tbl_map_single() { ... if (no_iotlb_memory) panic("Can not allocate SWIOTLB buffer earlier ..."); ... } (2) On the Cavium OCTEON platform arch/mips/cavium-octeon/dma-octeon.c void __init plat_swiotlb_setup(void) { ... octeon_swiotlb = memblock_alloc_low(swiotlbsize, PAGE_SIZE); if (!octeon_swiotlb) panic("%s: Failed to allocate %zu bytes align=%lx\n", __func__, swiotlbsize, PAGE_SIZE); ... } Because IO_TLB_DEFAULT_SIZE is 64M, if the rest size of low memory is less than 64M when call plat_swiotlb_setup(), we can easily reproduce the panic case. In order to reduce the possibility of kernel panic when failed to get IO TLB memory under CONFIG_SWIOTLB, it is better to allocate low memory as small as possible before plat_swiotlb_setup(), so make sparse_init() using top-down allocation. Reported-by: Juxin Gao Co-developed-by: Juxin Gao Signed-off-by: Juxin Gao Signed-off-by: Tiezhu Yang Signed-off-by: Thomas Bogendoerfer Signed-off-by: Sasha Levin