diff options
| author | Ravi Bangoria <ravi.bangoria@linux.ibm.com> | 2019-10-17 11:31:59 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2019-11-13 06:58:03 +0100 |
| commit | b57aeab811db07295f646808b1b17c312d17f57d (patch) | |
| tree | 4e2155005e5805bfa5c4074f9702a5634c973b1f /arch/powerpc/kernel/dawr.c | |
| parent | powerpc/watchpoint: Introduce macros for watchpoint length (diff) | |
| download | linux-b57aeab811db07295f646808b1b17c312d17f57d.tar.xz linux-b57aeab811db07295f646808b1b17c312d17f57d.zip | |
powerpc/watchpoint: Fix length calculation for unaligned target
Watchpoint match range is always doubleword(8 bytes) aligned on
powerpc. If the given range is crossing doubleword boundary, we need
to increase the length such that next doubleword also get
covered. Ex,
address len = 6 bytes
|=========.
|------------v--|------v--------|
| | | | | | | | | | | | | | | | |
|---------------|---------------|
<---8 bytes--->
In such case, current code configures hw as:
start_addr = address & ~HW_BREAKPOINT_ALIGN
len = 8 bytes
And thus read/write in last 4 bytes of the given range is ignored.
Fix this by including next doubleword in the length.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191017093204.7511-3-ravi.bangoria@linux.ibm.com
Diffstat (limited to 'arch/powerpc/kernel/dawr.c')
| -rw-r--r-- | arch/powerpc/kernel/dawr.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/arch/powerpc/kernel/dawr.c b/arch/powerpc/kernel/dawr.c index 5f66b95b6858..cc14aa6c4a1b 100644 --- a/arch/powerpc/kernel/dawr.c +++ b/arch/powerpc/kernel/dawr.c @@ -30,10 +30,10 @@ int set_dawr(struct arch_hw_breakpoint *brk) * DAWR length is stored in field MDR bits 48:53. Matches range in * doublewords (64 bits) baised by -1 eg. 0b000000=1DW and * 0b111111=64DW. - * brk->len is in bytes. + * brk->hw_len is in bytes. * This aligns up to double word size, shifts and does the bias. */ - mrd = ((brk->len + 7) >> 3) - 1; + mrd = ((brk->hw_len + 7) >> 3) - 1; dawrx |= (mrd & 0x3f) << (63 - 53); if (ppc_md.set_dawr) @@ -54,7 +54,7 @@ static ssize_t dawr_write_file_bool(struct file *file, const char __user *user_buf, size_t count, loff_t *ppos) { - struct arch_hw_breakpoint null_brk = {0, 0, 0}; + struct arch_hw_breakpoint null_brk = {0}; size_t rc; /* Send error to user if they hypervisor won't allow us to write DAWR */ |