kernel/linux.git/arch/powerpc/Kconfig.debug, branch v6.6.132

powerpc: allow PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=y

2023-07-03T06:07:55+00:00

In a randconfig with CONFIG_SERIAL_CPM=m and CONFIG_PPC_EARLY_DEBUG_CPM=y, there is a build error: ERROR: modpost: "udbg_putc" [drivers/tty/serial/cpm_uart/cpm_uart.ko] undefined! Prevent the build error by allowing PPC_EARLY_DEBUG_CPM only when SERIAL_CPM=y. Fixes: c374e00e17f1 ("[POWERPC] Add early debug console for CPM serial ports.") Signed-off-by: Randy Dunlap Reviewed-by: Pali Rohár Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://msgid.link/20230701054714.30512-1-rdunlap@infradead.org

powerpc: Add support for early debugging via Serial 16550 console

2022-09-28T09:22:09+00:00

Currently powerpc early debugging contains lot of platform specific options, but does not support standard UART / serial 16550 console. Later legacy_serial.c code supports registering UART as early debug console from device tree but it is not early during booting, but rather later after machine description code finishes. So for real early debugging via UART is current code unsuitable. Add support for new early debugging option CONFIG_PPC_EARLY_DEBUG_16550 which enable Serial 16550 console on address defined by new option CONFIG_PPC_EARLY_DEBUG_16550_PHYSADDR and by stride by option CONFIG_PPC_EARLY_DEBUG_16550_STRIDE. With this change it is possible to debug powerpc machine descriptor code. For example this early debugging code can print on serial console also "No suitable machine description found" error which is done before legacy_serial.c code. Signed-off-by: Pali Rohár Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220822231501.16827-1-pali@kernel.org

powerpc: Kconfig.debug: Remove extra empty line

2022-06-29T09:43:16+00:00

Remove a stray extra empty line. Signed-off-by: Juerg Haefliger Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220526065737.86370-3-juerg.haefliger@canonical.com

powerpc/64e: KASAN Full support for BOOK3E/64

2022-06-29T07:04:15+00:00

We now have memory organised in a way that allows implementing KASAN. Unlike book3s/64, book3e always has translation active so the only thing needed to use KASAN is to setup an early zero shadow mapping just after setting a stack pointer and before calling early_setup(). The memory layout is now as follows +------------------------+ Kernel virtual map end (0xc000200000000000) | | | 16TB of KASAN map | | | +------------------------+ Kernel KASAN shadow map start | | | 16TB of IO map | | | +------------------------+ Kernel IO map start | | | 16TB of vmemmap | | | +------------------------+ Kernel vmemmap start | | | 16TB of vmap | | | +------------------------+ Kernel virt start (0xc000100000000000) | | | 64TB of linear mem | | | +------------------------+ Kernel linear (0xc.....) Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/0bef8beda27baf71e3b9e8b13e620fba6e19499b.1656427701.git.christophe.leroy@csgroup.eu

powerpc: Book3S 64-bit outline-only KASAN support

2022-05-22T05:58:29+00:00

Implement a limited form of KASAN for Book3S 64-bit machines running under the Radix MMU, supporting only outline mode. - Enable the compiler instrumentation to check addresses and maintain the shadow region. (This is the guts of KASAN which we can easily reuse.) - Require kasan-vmalloc support to handle modules and anything else in vmalloc space. - KASAN needs to be able to validate all pointer accesses, but we can't instrument all kernel addresses - only linear map and vmalloc. On boot, set up a single page of read-only shadow that marks all iomap and vmemmap accesses as valid. - Document KASAN in powerpc docs. Background ---------- KASAN support on Book3S is a bit tricky to get right: - It would be good to support inline instrumentation so as to be able to catch stack issues that cannot be caught with outline mode. - Inline instrumentation requires a fixed offset. - Book3S runs code with translations off ("real mode") during boot, including a lot of generic device-tree parsing code which is used to determine MMU features. [ppc64 mm note: The kernel installs a linear mapping at effective address c000...-c008.... This is a one-to-one mapping with physical memory from 0000... onward. Because of how memory accesses work on powerpc 64-bit Book3S, a kernel pointer in the linear map accesses the same memory both with translations on (accessing as an 'effective address'), and with translations off (accessing as a 'real address'). This works in both guests and the hypervisor. For more details, see s5.7 of Book III of version 3 of the ISA, in particular the Storage Control Overview, s5.7.3, and s5.7.5 - noting that this KASAN implementation currently only supports Radix.] - Some code - most notably a lot of KVM code - also runs with translations off after boot. - Therefore any offset has to point to memory that is valid with translations on or off. One approach is just to give up on inline instrumentation. This way boot-time checks can be delayed until after the MMU is set is up, and we can just not instrument any code that runs with translations off after booting. Take this approach for now and require outline instrumentation. Previous attempts allowed inline instrumentation. However, they came with some unfortunate restrictions: only physically contiguous memory could be used and it had to be specified at compile time. Maybe we can do better in the future. [paulus@ozlabs.org - Rebased onto 5.17. Note that a kernel with CONFIG_KASAN=y will crash during boot on a machine using HPT translation because not all the entry points to the generic KASAN code are protected with a call to kasan_arch_is_ready().] Originally-by: Balbir Singh # ppc64 out-of-line radix version Signed-off-by: Daniel Axtens Signed-off-by: Paul Mackerras [mpe: Update copyright year and comment formatting] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/YoTE69OQwiG7z+Gu@cleo

powerpc/ptdump: Convert powerpc to GENERIC_PTDUMP

2021-08-25T03:35:48+00:00

This patch converts powerpc to the generic PTDUMP implementation. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/03166d569526be70214fe9370a7bad219d2f41c8.1625762907.git.christophe.leroy@csgroup.eu

powerpc: Make PPC_IRQ_SOFT_MASK_DEBUG depend on PPC64

2021-06-24T14:07:09+00:00

32-bit platforms don't have irq soft masking. Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210623032909.826010-1-npiggin@gmail.com

powerpc/64s: avoid reloading (H)SRR registers if they are still valid

2021-06-24T14:06:55+00:00

When an interrupt is taken, the SRR registers are set to return to where it left off. Unless they are modified in the meantime, or the return address or MSR are modified, there is no need to reload these registers when returning from interrupt. Introduce per-CPU flags that track the validity of SRR and HSRR registers. These are cleared when returning from interrupt, when using the registers for something else (e.g., OPAL calls), when adjusting the return address or MSR of a context, and when context switching (which changes the return address and MSR). This improves the performance of interrupt returns. Signed-off-by: Nicholas Piggin [mpe: Fold in fixup patch from Nick] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210617155116.2167984-5-npiggin@gmail.com

powerpc: iommu: fix build when neither PCI or IBMVIO is set

2021-04-08T11:17:46+00:00

When neither CONFIG_PCI nor CONFIG_IBMVIO is set/enabled, iommu.c has a build error. The fault injection code is not useful in that kernel config, so make the FAIL_IOMMU option depend on PCI || IBMVIO. Prevents this build error (warning escalated to error): ../arch/powerpc/kernel/iommu.c:178:30: error: 'fail_iommu_bus_notifier' defined but not used [-Werror=unused-variable] 178 | static struct notifier_block fail_iommu_bus_notifier = { Fixes: d6b9a81b2a45 ("powerpc: IOMMU fault injection") Reported-by: kernel test robot Suggested-by: Michael Ellerman Signed-off-by: Randy Dunlap Acked-by: Randy Dunlap # build-tested Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20210404192623.10697-1-rdunlap@infradead.org

powerpc/xmon: Select CONSOLE_POLL for the 8xx

2021-01-31T11:35:51+00:00

Powerpc 8xx requires CONSOLE_POLL to get udbg_putc() and udbg_getc() in CPM uart driver. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/3d10a274516e9be8c4b0dc679a2840cdc1588872.1608716197.git.christophe.leroy@csgroup.eu