From 09752a12f430f58523fb6f435f5e30e4048fcfb2 Mon Sep 17 00:00:00 2001 From: Jason Gunthorpe Date: Fri, 18 Apr 2014 14:19:51 +0200 Subject: [PATCH] bus: mvebu-mbus: Avoid setting an undefined window size The mbus hardware requires a power of two size, and size aligned base. Currently, if a non-power of two is passed in to the low level routines they configure the register in a way that results in undefined behaviour. Call WARN and return EINVAL instead. Also, update the debugfs routines to show a message if there is an invalid register setting. All together this makes the recent problems with silent failure of PCI very obvious, noisy and debuggable. Signed-off-by: Jason Gunthorpe Signed-off-by: Thomas Petazzoni Link: https://lkml.kernel.org/r/1397823593-1932-6-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by: Jason Cooper --- drivers/bus/mvebu-mbus.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/drivers/bus/mvebu-mbus.c b/drivers/bus/mvebu-mbus.c index 293e2e0a0a87..afee0f731111 100644 --- a/drivers/bus/mvebu-mbus.c +++ b/drivers/bus/mvebu-mbus.c @@ -56,6 +56,7 @@ #include #include #include +#include /* * DDR target is the same on all platforms. @@ -266,6 +267,17 @@ static int mvebu_mbus_setup_window(struct mvebu_mbus_state *mbus, mbus->soc->win_cfg_offset(win); u32 ctrl, remap_addr; + if (!is_power_of_2(size)) { + WARN(true, "Invalid MBus window size: 0x%zx\n", size); + return -EINVAL; + } + + if ((base & (phys_addr_t)(size - 1)) != 0) { + WARN(true, "Invalid MBus base/size: %pa len 0x%zx\n", &base, + size); + return -EINVAL; + } + ctrl = ((size - 1) & WIN_CTRL_SIZE_MASK) | (attr << WIN_CTRL_ATTR_SHIFT) | (target << WIN_CTRL_TGT_SHIFT) | @@ -413,6 +425,10 @@ static int mvebu_devs_debug_show(struct seq_file *seq, void *v) win, (unsigned long long)wbase, (unsigned long long)(wbase + wsize), wtarget, wattr); + if (!is_power_of_2(wsize) || + ((wbase & (u64)(wsize - 1)) != 0)) + seq_puts(seq, " (Invalid base/size!!)"); + if (win < mbus->soc->num_remappable_wins) { seq_printf(seq, " (remap %016llx)\n", (unsigned long long)wremap); -- 2.20.1