lkml.org 
[lkml]   [2020]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH AUTOSEL 5.5 077/106] csky: Fixup cpu speculative execution to IO area
    Date
    From: Guo Ren <guoren@linux.alibaba.com>

    [ Upstream commit aefd9461d34a1b0a2acad0750c43216c1c27b9d4 ]

    For the memory size ( > 512MB, < 1GB), the MSA setting is:

    - SSEG0: PHY_START , PHY_START + 512MB
    - SSEG1: PHY_START + 512MB, PHY_START + 1GB

    But the real memory is no more than 1GB, there is a gap between the
    end size of memory and border of 1GB. CPU could speculatively
    execute to that gap and if the gap of the bus couldn't respond to
    the CPU request, then the crash will happen.

    Now make the setting with:

    - SSEG0: PHY_START , PHY_START + 512MB (no change)
    - SSEG1: Disabled (We use highmem to use the memory of 512MB~1GB)

    We also deprecated zhole_szie[] settings, it's only used by arm
    style CPUs. All memory gap should use Reserved setting of dts in
    csky system.

    Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
    Signed-off-by: Sasha Levin <sashal@kernel.org>
    ---
    arch/csky/abiv1/inc/abi/entry.h | 5 +--
    arch/csky/abiv2/inc/abi/entry.h | 7 ++--
    arch/csky/kernel/head.S | 5 +++
    arch/csky/kernel/setup.c | 63 ++++++++-------------------------
    arch/csky/kernel/smp.c | 3 ++
    5 files changed, 25 insertions(+), 58 deletions(-)

    diff --git a/arch/csky/abiv1/inc/abi/entry.h b/arch/csky/abiv1/inc/abi/entry.h
    index f35a9f3315ee6..5056ebb902d18 100644
    --- a/arch/csky/abiv1/inc/abi/entry.h
    +++ b/arch/csky/abiv1/inc/abi/entry.h
    @@ -172,10 +172,7 @@
    addi r6, 0xe
    cpwcr r6, cpcr30

    - lsri r6, 28
    - addi r6, 2
    - lsli r6, 28
    - addi r6, 0xe
    + movi r6, 0
    cpwcr r6, cpcr31
    .endm

    diff --git a/arch/csky/abiv2/inc/abi/entry.h b/arch/csky/abiv2/inc/abi/entry.h
    index 94a7a58765dff..111973c6c713f 100644
    --- a/arch/csky/abiv2/inc/abi/entry.h
    +++ b/arch/csky/abiv2/inc/abi/entry.h
    @@ -230,11 +230,8 @@
    addi r6, 0x1ce
    mtcr r6, cr<30, 15> /* Set MSA0 */

    - lsri r6, 28
    - addi r6, 2
    - lsli r6, 28
    - addi r6, 0x1ce
    - mtcr r6, cr<31, 15> /* Set MSA1 */
    + movi r6, 0
    + mtcr r6, cr<31, 15> /* Clr MSA1 */

    /* enable MMU */
    mfcr r6, cr18
    diff --git a/arch/csky/kernel/head.S b/arch/csky/kernel/head.S
    index 61989f9241c02..17ed9d2504807 100644
    --- a/arch/csky/kernel/head.S
    +++ b/arch/csky/kernel/head.S
    @@ -21,6 +21,11 @@ END(_start)
    ENTRY(_start_smp_secondary)
    SETUP_MMU

    + /* copy msa1 from CPU0 */
    + lrw r6, secondary_msa1
    + ld.w r6, (r6, 0)
    + mtcr r6, cr<31, 15>
    +
    /* set stack point */
    lrw r6, secondary_stack
    ld.w r6, (r6, 0)
    diff --git a/arch/csky/kernel/setup.c b/arch/csky/kernel/setup.c
    index 23ee604aafdb6..2c1e253abb74c 100644
    --- a/arch/csky/kernel/setup.c
    +++ b/arch/csky/kernel/setup.c
    @@ -24,26 +24,9 @@ struct screen_info screen_info = {
    };
    #endif

    -phys_addr_t __init_memblock memblock_end_of_REG0(void)
    -{
    - return (memblock.memory.regions[0].base +
    - memblock.memory.regions[0].size);
    -}
    -
    -phys_addr_t __init_memblock memblock_start_of_REG1(void)
    -{
    - return memblock.memory.regions[1].base;
    -}
    -
    -size_t __init_memblock memblock_size_of_REG1(void)
    -{
    - return memblock.memory.regions[1].size;
    -}
    -
    static void __init csky_memblock_init(void)
    {
    unsigned long zone_size[MAX_NR_ZONES];
    - unsigned long zhole_size[MAX_NR_ZONES];
    signed long size;

    memblock_reserve(__pa(_stext), _end - _stext);
    @@ -57,54 +40,36 @@ static void __init csky_memblock_init(void)
    memblock_dump_all();

    memset(zone_size, 0, sizeof(zone_size));
    - memset(zhole_size, 0, sizeof(zhole_size));

    min_low_pfn = PFN_UP(memblock_start_of_DRAM());
    - max_pfn = PFN_DOWN(memblock_end_of_DRAM());
    -
    - max_low_pfn = PFN_UP(memblock_end_of_REG0());
    - if (max_low_pfn == 0)
    - max_low_pfn = max_pfn;
    + max_low_pfn = max_pfn = PFN_DOWN(memblock_end_of_DRAM());

    size = max_pfn - min_low_pfn;

    - if (memblock.memory.cnt > 1) {
    - zone_size[ZONE_NORMAL] =
    - PFN_DOWN(memblock_start_of_REG1()) - min_low_pfn;
    - zhole_size[ZONE_NORMAL] =
    - PFN_DOWN(memblock_start_of_REG1()) - max_low_pfn;
    + if (size <= PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET))
    + zone_size[ZONE_NORMAL] = size;
    + else if (size < PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET)) {
    + zone_size[ZONE_NORMAL] =
    + PFN_DOWN(SSEG_SIZE - PHYS_OFFSET_OFFSET);
    + max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
    } else {
    - if (size <= PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET))
    - zone_size[ZONE_NORMAL] = max_pfn - min_low_pfn;
    - else {
    - zone_size[ZONE_NORMAL] =
    + zone_size[ZONE_NORMAL] =
    PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
    - max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
    - }
    + max_low_pfn = min_low_pfn + zone_size[ZONE_NORMAL];
    + write_mmu_msa1(read_mmu_msa0() + SSEG_SIZE);
    }

    #ifdef CONFIG_HIGHMEM
    - size = 0;
    - if (memblock.memory.cnt > 1) {
    - size = PFN_DOWN(memblock_size_of_REG1());
    - highstart_pfn = PFN_DOWN(memblock_start_of_REG1());
    - } else {
    - size = max_pfn - min_low_pfn -
    - PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
    - highstart_pfn = min_low_pfn +
    - PFN_DOWN(LOWMEM_LIMIT - PHYS_OFFSET_OFFSET);
    - }
    -
    - if (size > 0)
    - zone_size[ZONE_HIGHMEM] = size;
    + zone_size[ZONE_HIGHMEM] = max_pfn - max_low_pfn;

    - highend_pfn = max_pfn;
    + highstart_pfn = max_low_pfn;
    + highend_pfn = max_pfn;
    #endif
    memblock_set_current_limit(PFN_PHYS(max_low_pfn));

    dma_contiguous_reserve(0);

    - free_area_init_node(0, zone_size, min_low_pfn, zhole_size);
    + free_area_init_node(0, zone_size, min_low_pfn, NULL);
    }

    void __init setup_arch(char **cmdline_p)
    diff --git a/arch/csky/kernel/smp.c b/arch/csky/kernel/smp.c
    index 0bb0954d55709..de61feb4b6df2 100644
    --- a/arch/csky/kernel/smp.c
    +++ b/arch/csky/kernel/smp.c
    @@ -156,6 +156,8 @@ volatile unsigned int secondary_hint;
    volatile unsigned int secondary_ccr;
    volatile unsigned int secondary_stack;

    +unsigned long secondary_msa1;
    +
    int __cpu_up(unsigned int cpu, struct task_struct *tidle)
    {
    unsigned long mask = 1 << cpu;
    @@ -164,6 +166,7 @@ int __cpu_up(unsigned int cpu, struct task_struct *tidle)
    (unsigned int) task_stack_page(tidle) + THREAD_SIZE - 8;
    secondary_hint = mfcr("cr31");
    secondary_ccr = mfcr("cr18");
    + secondary_msa1 = read_mmu_msa1();

    /*
    * Because other CPUs are in reset status, we must flush data
    --
    2.20.1
    \
     
     \ /
      Last update: 2020-04-15 14:39    [W:4.173 / U:0.020 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site