From a4780adeefd042482f624f5e0d577bf9cdcbb760 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Hentschel?= Date: Tue, 18 Jun 2013 23:23:26 +0100 Subject: ARM: 7735/2: Preserve the user r/w register TPIDRURW on context switch and fork MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Since commit 6a1c53124aa1 the user writeable TLS register was zeroed to prevent it from being used as a covert channel between two tasks. There are more and more applications coming to Windows RT, Wine could support them, but mostly they expect to have the thread environment block (TEB) in TPIDRURW. This patch preserves that register per thread instead of clearing it. Unlike the TPIDRURO, which is already switched, the TPIDRURW can be updated from userspace so needs careful treatment in the case that we modify TPIDRURW and call fork(). To avoid this we must always read TPIDRURW in copy_thread. Signed-off-by: André Hentschel Signed-off-by: Will Deacon Signed-off-by: Jonathan Austin Signed-off-by: Russell King --- arch/arm/kernel/process.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index f21970316836..087064148ebf 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -39,6 +39,7 @@ #include #include #include +#include #ifdef CONFIG_CC_STACKPROTECTOR #include @@ -343,7 +344,8 @@ copy_thread(unsigned long clone_flags, unsigned long stack_start, clear_ptrace_hw_breakpoint(p); if (clone_flags & CLONE_SETTLS) - thread->tp_value = childregs->ARM_r3; + thread->tp_value[0] = childregs->ARM_r3; + thread->tp_value[1] = get_tpuser(); thread_notify(THREAD_NOTIFY_COPY, thread); -- cgit v1.2.3 From 16d6d5b00ee75307bab7e4ede9452c97b28f30e2 Mon Sep 17 00:00:00 2001 From: Robin Holt Date: Mon, 8 Jul 2013 16:01:39 -0700 Subject: reboot: arm: prepare reboot_mode for moving to generic kernel code Prepare for the moving the parsing of reboot= to the generic kernel code by making reboot_mode into a more generic form. Signed-off-by: Robin Holt Cc: Russell King Cc: Russ Anderson Cc: Robin Holt Cc: H. Peter Anvin Cc: Guan Xuetao Acked-by: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm/kernel/process.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 7f1efcd4a6e9..2d544062fd7d 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -175,14 +175,14 @@ void arch_cpu_idle(void) default_idle(); } -static char reboot_mode = 'h'; +enum reboot_mode reboot_mode = REBOOT_HARD; -int __init reboot_setup(char *str) +static int __init reboot_setup(char *str) { - reboot_mode = str[0]; + if ('s' == str[0]) + reboot_mode = REBOOT_SOFT; return 1; } - __setup("reboot=", reboot_setup); /* -- cgit v1.2.3 From 7b6d864b48d95e6ea1df7df64475b9cb9616dcf9 Mon Sep 17 00:00:00 2001 From: Robin Holt Date: Mon, 8 Jul 2013 16:01:40 -0700 Subject: reboot: arm: change reboot_mode to use enum reboot_mode Preparing to move the parsing of reboot= to generic kernel code forces the change in reboot_mode handling to use the enum. [akpm@linux-foundation.org: fix arch/arm/mach-socfpga/socfpga.c] Signed-off-by: Robin Holt Cc: Russell King Cc: Russ Anderson Cc: Robin Holt Cc: H. Peter Anvin Cc: Guan Xuetao Acked-by: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm/kernel/process.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 2d544062fd7d..b7fdd864c839 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #include @@ -113,7 +114,7 @@ void soft_restart(unsigned long addr) BUG(); } -static void null_restart(char mode, const char *cmd) +static void null_restart(enum reboot_mode reboot_mode, const char *cmd) { } @@ -123,7 +124,7 @@ static void null_restart(char mode, const char *cmd) void (*pm_power_off)(void); EXPORT_SYMBOL(pm_power_off); -void (*arm_pm_restart)(char str, const char *cmd) = null_restart; +void (*arm_pm_restart)(enum reboot_mode reboot_mode, const char *cmd) = null_restart; EXPORT_SYMBOL_GPL(arm_pm_restart); /* -- cgit v1.2.3 From 1b3a5d02ee070c8f9943333b9b6370f486601e0f Mon Sep 17 00:00:00 2001 From: Robin Holt Date: Mon, 8 Jul 2013 16:01:42 -0700 Subject: reboot: move arch/x86 reboot= handling to generic kernel Merge together the unicore32, arm, and x86 reboot= command line parameter handling. Signed-off-by: Robin Holt Cc: H. Peter Anvin Cc: Russell King Cc: Guan Xuetao Cc: Russ Anderson Cc: Robin Holt Acked-by: Ingo Molnar Acked-by: Guan Xuetao Acked-by: Russell King Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm/kernel/process.c | 10 ---------- 1 file changed, 10 deletions(-) (limited to 'arch/arm/kernel/process.c') diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index b7fdd864c839..d3ca4f6915af 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -176,16 +176,6 @@ void arch_cpu_idle(void) default_idle(); } -enum reboot_mode reboot_mode = REBOOT_HARD; - -static int __init reboot_setup(char *str) -{ - if ('s' == str[0]) - reboot_mode = REBOOT_SOFT; - return 1; -} -__setup("reboot=", reboot_setup); - /* * Called by kexec, immediately prior to machine_kexec(). * -- cgit v1.2.3