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| author | Bhupesh Sharma <bhsharma@redhat.com> | 2020-05-14 00:22:37 +0530 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-07-02 17:56:49 +0100 |
| commit | bbdbc11804ff0b4130e7550113b452e96a74d16e (patch) | |
| tree | d2541374bf8be92d105309b05ba8fc90f6b6ff05 | |
| parent | 1d50e5d0c5052446cb85a3bf11fe8ba4e8d770ca (diff) | |
| download | linux-bbdbc11804ff0b4130e7550113b452e96a74d16e.tar.gz linux-bbdbc11804ff0b4130e7550113b452e96a74d16e.tar.bz2 linux-bbdbc11804ff0b4130e7550113b452e96a74d16e.zip | |
arm64/crash_core: Export TCR_EL1.T1SZ in vmcoreinfo
TCR_EL1.TxSZ, which controls the VA space size, is configured by a
single kernel image to support either 48-bit or 52-bit VA space.
If the ARMv8.2-LVA optional feature is present and we are running
with a 64KB page size, then it is possible to use 52-bits of address
space for both userspace and kernel addresses. However, any kernel
binary that supports 52-bit must also be able to fall back to 48-bit
at early boot time if the hardware feature is not present.
Since TCR_EL1.T1SZ indicates the size of the memory region addressed by
TTBR1_EL1, export the same in vmcoreinfo. User-space utilities like
makedumpfile and crash-utility need to read this value from vmcoreinfo
for determining if a virtual address lies in the linear map range.
While at it also add documentation for TCR_EL1.T1SZ variable being
added to vmcoreinfo.
It indicates the size offset of the memory region addressed by
TTBR1_EL1.
Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Tested-by: John Donnelly <john.p.donnelly@oracle.com>
Tested-by: Kamlakant Patel <kamlakantp@marvell.com>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: James Morse <james.morse@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Cc: James Morse <james.morse@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Steve Capper <steve.capper@arm.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: kexec@lists.infradead.org
Link: https://lore.kernel.org/r/1589395957-24628-3-git-send-email-bhsharma@redhat.com
[catalin.marinas@arm.com: removed vabits_actual from the commit log]
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
| -rw-r--r-- | Documentation/admin-guide/kdump/vmcoreinfo.rst | 11 | ||||
| -rw-r--r-- | arch/arm64/include/asm/pgtable-hwdef.h | 1 | ||||
| -rw-r--r-- | arch/arm64/kernel/crash_core.c | 10 |
3 files changed, 22 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kdump/vmcoreinfo.rst b/Documentation/admin-guide/kdump/vmcoreinfo.rst index 2a632020f809..2baad0bfb09d 100644 --- a/Documentation/admin-guide/kdump/vmcoreinfo.rst +++ b/Documentation/admin-guide/kdump/vmcoreinfo.rst @@ -404,6 +404,17 @@ KERNELPACMASK The mask to extract the Pointer Authentication Code from a kernel virtual address. +TCR_EL1.T1SZ +------------ + +Indicates the size offset of the memory region addressed by TTBR1_EL1. +The region size is 2^(64-T1SZ) bytes. + +TTBR1_EL1 is the table base address register specified by ARMv8-A +architecture which is used to lookup the page-tables for the Virtual +addresses in the higher VA range (refer to ARMv8 ARM document for +more details). + arm === diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index 9c91a8f93a0e..9a757d724974 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -216,6 +216,7 @@ #define TCR_TxSZ(x) (TCR_T0SZ(x) | TCR_T1SZ(x)) #define TCR_TxSZ_WIDTH 6 #define TCR_T0SZ_MASK (((UL(1) << TCR_TxSZ_WIDTH) - 1) << TCR_T0SZ_OFFSET) +#define TCR_T1SZ_MASK (((UL(1) << TCR_TxSZ_WIDTH) - 1) << TCR_T1SZ_OFFSET) #define TCR_EPD0_SHIFT 7 #define TCR_EPD0_MASK (UL(1) << TCR_EPD0_SHIFT) diff --git a/arch/arm64/kernel/crash_core.c b/arch/arm64/kernel/crash_core.c index 1f646b07e3e9..314391a156ee 100644 --- a/arch/arm64/kernel/crash_core.c +++ b/arch/arm64/kernel/crash_core.c @@ -7,6 +7,14 @@ #include <linux/crash_core.h> #include <asm/cpufeature.h> #include <asm/memory.h> +#include <asm/pgtable-hwdef.h> + +static inline u64 get_tcr_el1_t1sz(void); + +static inline u64 get_tcr_el1_t1sz(void) +{ + return (read_sysreg(tcr_el1) & TCR_T1SZ_MASK) >> TCR_T1SZ_OFFSET; +} void arch_crash_save_vmcoreinfo(void) { @@ -16,6 +24,8 @@ void arch_crash_save_vmcoreinfo(void) kimage_voffset); vmcoreinfo_append_str("NUMBER(PHYS_OFFSET)=0x%llx\n", PHYS_OFFSET); + vmcoreinfo_append_str("NUMBER(TCR_EL1_T1SZ)=0x%llx\n", + get_tcr_el1_t1sz()); vmcoreinfo_append_str("KERNELOFFSET=%lx\n", kaslr_offset()); vmcoreinfo_append_str("NUMBER(KERNELPACMASK)=0x%llx\n", system_supports_address_auth() ? |